<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html>
<head>
<!-- Generated by HsColour, http://www.cs.york.ac.uk/fp/darcs/hscolour/ -->
<title>src/System/Log/Logger.hs</title>
<link type='text/css' rel='stylesheet' href='hscolour.css' />
</head>
<body>
<pre><a name="line-1"></a><span class='hs-comment'>{-# OPTIONS -fglasgow-exts #-}</span>
<a name="line-2"></a><span class='hs-comment'>{- arch-tag: Logger main definition
<a name="line-3"></a>Copyright (C) 2004-2009 John Goerzen <jgoerzen@complete.org>
<a name="line-4"></a>
<a name="line-5"></a>This program is free software; you can redistribute it and/or modify
<a name="line-6"></a>it under the terms of the GNU Lesser General Public License as published by
<a name="line-7"></a>the Free Software Foundation; either version 2.1 of the License, or
<a name="line-8"></a>(at your option) any later version.
<a name="line-9"></a>
<a name="line-10"></a>This program is distributed in the hope that it will be useful,
<a name="line-11"></a>but WITHOUT ANY WARRANTY; without even the implied warranty of
<a name="line-12"></a>MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
<a name="line-13"></a>GNU Lesser General Public License for more details.
<a name="line-14"></a>
<a name="line-15"></a>You should have received a copy of the GNU Lesser General Public License
<a name="line-16"></a>along with this program; if not, write to the Free Software
<a name="line-17"></a>Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
<a name="line-18"></a>-}</span>
<a name="line-19"></a>
<a name="line-20"></a><span class='hs-comment'>{- |
<a name="line-21"></a> Module : System.Log.Logger
<a name="line-22"></a> Copyright : Copyright (C) 2004-2009 John Goerzen
<a name="line-23"></a> License : GNU LGPL, version 2.1 or above
<a name="line-24"></a>
<a name="line-25"></a> Maintainer : John Goerzen <jgoerzen@complete.org>
<a name="line-26"></a> Stability : provisional
<a name="line-27"></a> Portability: portable
<a name="line-28"></a>
<a name="line-29"></a>Haskell Logging Framework, Primary Interface
<a name="line-30"></a>
<a name="line-31"></a>Written by John Goerzen, jgoerzen\@complete.org
<a name="line-32"></a>
<a name="line-33"></a>Welcome to the error and information logging system for Haskell.
<a name="line-34"></a>
<a name="line-35"></a>This system is patterned after Python\'s @logging@ module,
<a name="line-36"></a><<a href="http://www.python.org/doc/current/lib/module-logging.html">http://www.python.org/doc/current/lib/module-logging.html</a>> and some of
<a name="line-37"></a>the documentation here was based on documentation there.
<a name="line-38"></a>
<a name="line-39"></a>To log a message, you perform operations on 'Logger's. Each 'Logger' has a
<a name="line-40"></a>name, and they are arranged hierarchically. Periods serve as separators.
<a name="line-41"></a>Therefore, a 'Logger' named \"foo\" is the parent of loggers \"foo.printing\",
<a name="line-42"></a>\"foo.html\", and \"foo.io\". These names can be anything you want. They're
<a name="line-43"></a>used to indicate the area of an application or library in which a logged
<a name="line-44"></a>message originates. Later you will see how you can use this concept to
<a name="line-45"></a>fine-tune logging behaviors based on specific application areas.
<a name="line-46"></a>
<a name="line-47"></a>You can also tune logging behaviors based upon how important a message is.
<a name="line-48"></a>Each message you log will have an importance associated with it. The different
<a name="line-49"></a>importance levels are given by the 'Priority' type. I've also provided
<a name="line-50"></a>some convenient functions that correspond to these importance levels:
<a name="line-51"></a>'debugM' through 'emergencyM' log messages with the specified importance.
<a name="line-52"></a>
<a name="line-53"></a>Now, an importance level (or 'Priority')
<a name="line-54"></a>is associated not just with a particular message but also
<a name="line-55"></a>with a 'Logger'. If the 'Priority' of a given log message is lower than
<a name="line-56"></a>the 'Priority' configured in the 'Logger', that message is ignored. This
<a name="line-57"></a>way, you can globally control how verbose your logging output is.
<a name="line-58"></a>
<a name="line-59"></a>Now, let's follow what happens under the hood when you log a message. We'll
<a name="line-60"></a>assume for the moment that you are logging something with a high enough
<a name="line-61"></a>'Priority' that it passes the test in your 'Logger'. In your code, you'll
<a name="line-62"></a>call 'logM' or something like 'debugM' to log the message. Your 'Logger'
<a name="line-63"></a>decides to accept the message. What next?
<a name="line-64"></a>
<a name="line-65"></a>Well, we also have a notion of /handlers/ ('LogHandler's, to be precise).
<a name="line-66"></a>A 'LogHandler' is a thing that takes a message and sends it somewhere.
<a name="line-67"></a>That \"somewhere\" may be your screen (via standard error), your system's
<a name="line-68"></a>logging infrastructure (via syslog), a file, or other things. Each
<a name="line-69"></a>'Logger' can have zero or more 'LogHandler's associated with it. When your
<a name="line-70"></a>'Logger' has a message to log, it passes it to every 'LogHandler' it knows
<a name="line-71"></a>of to process. What's more, it is also passed to /all handlers of all
<a name="line-72"></a>ancestors of the Logger/, regardless of whether those 'Logger's would
<a name="line-73"></a>normally have passed on the message.
<a name="line-74"></a>
<a name="line-75"></a>Each 'Logger' can /optionally/ store a 'Priority'. If a given Logger does
<a name="line-76"></a>not have a Priority, and you log a message to that logger, the system will
<a name="line-77"></a>use the priority of the parent of the destination logger to find out whether
<a name="line-78"></a>to log the message. If the parent has no priority associated with it,
<a name="line-79"></a>the system continues walking up the tree to figure out a priority until
<a name="line-80"></a>it hits the root logger. In this way, you can easily adjust the priority
<a name="line-81"></a>of an entire subtree of loggers. When a new logger is created, it has no
<a name="line-82"></a>priority by default. The exception is the root logger, which has a WARNING
<a name="line-83"></a>priority by default.
<a name="line-84"></a>
<a name="line-85"></a>To give you one extra little knob to turn, 'LogHandler's can also have
<a name="line-86"></a>importance levels ('Priority') associated with them in the same way
<a name="line-87"></a>that 'Logger's do. They act just like the 'Priority' value in the
<a name="line-88"></a>'Logger's -- as a filter. It's useful, for instance, to make sure that
<a name="line-89"></a>under no circumstances will a mere 'DEBUG' message show up in your syslog.
<a name="line-90"></a>
<a name="line-91"></a>There are three built-in handlers given in two built-in modules:
<a name="line-92"></a>"System.Log.Handler.Simple" and "System.Log.Handler.Syslog".
<a name="line-93"></a>
<a name="line-94"></a>There is a special logger known as the /root logger/ that sits at the top
<a name="line-95"></a>of the logger hierarchy. It is always present, and handlers attached
<a name="line-96"></a>there will be called for every message. You can use 'getRootLogger' to get
<a name="line-97"></a>it or 'rootLoggerName' to work with it by name.
<a name="line-98"></a>
<a name="line-99"></a>The formatting of log messages may be customized by setting a 'LogFormatter'
<a name="line-100"></a>on the desired 'LogHandler'. There are a number of simple formatters defined
<a name="line-101"></a>in "System.Log.Formatter", which may be used directly, or extend to create
<a name="line-102"></a>your own formatter.
<a name="line-103"></a>
<a name="line-104"></a>Here's an example to illustrate some of these concepts:
<a name="line-105"></a>
<a name="line-106"></a>> import System.Log.Logger
<a name="line-107"></a>> import System.Log.Handler.Syslog
<a name="line-108"></a>> import System.Log.Handler.Simple
<a name="line-109"></a>> import System.Log.Handler (setFormatter)
<a name="line-110"></a>> import System.Log.Formatter
<a name="line-111"></a>>
<a name="line-112"></a>> -- By default, all messages of level WARNING and above are sent to stderr.
<a name="line-113"></a>> -- Everything else is ignored.
<a name="line-114"></a>>
<a name="line-115"></a>> -- "MyApp.Component" is an arbitrary string; you can tune
<a name="line-116"></a>> -- logging behavior based on it later.
<a name="line-117"></a>> main = do
<a name="line-118"></a>> debugM "MyApp.Component" "This is a debug message -- never to be seen"
<a name="line-119"></a>> warningM "MyApp.Component2" "Something Bad is about to happen."
<a name="line-120"></a>>
<a name="line-121"></a>> -- Copy everything to syslog from here on out.
<a name="line-122"></a>> s <- openlog "SyslogStuff" [PID] USER DEBUG
<a name="line-123"></a>> updateGlobalLogger rootLoggerName (addHandler s)
<a name="line-124"></a>>
<a name="line-125"></a>> errorM "MyApp.Component" "This is going to stderr and syslog."
<a name="line-126"></a>>
<a name="line-127"></a>> -- Now we'd like to see everything from BuggyComponent
<a name="line-128"></a>> -- at DEBUG or higher go to syslog and stderr.
<a name="line-129"></a>> -- Also, we'd like to still ignore things less than
<a name="line-130"></a>> -- WARNING in other areas.
<a name="line-131"></a>> --
<a name="line-132"></a>> -- So, we adjust the Logger for MyApp.BuggyComponent.
<a name="line-133"></a>>
<a name="line-134"></a>> updateGlobalLogger "MyApp.BuggyComponent"
<a name="line-135"></a>> (setLevel DEBUG)
<a name="line-136"></a>>
<a name="line-137"></a>> -- This message will go to syslog and stderr
<a name="line-138"></a>> debugM "MyApp.BuggyComponent" "This buggy component is buggy"
<a name="line-139"></a>>
<a name="line-140"></a>> -- This message will go to syslog and stderr too.
<a name="line-141"></a>> warningM "MyApp.BuggyComponent" "Still Buggy"
<a name="line-142"></a>>
<a name="line-143"></a>> -- This message goes nowhere.
<a name="line-144"></a>> debugM "MyApp.WorkingComponent" "Hello"
<a name="line-145"></a>>
<a name="line-146"></a>> -- Now we decide we'd also like to log everything from BuggyComponent at DEBUG
<a name="line-147"></a>> -- or higher to a file for later diagnostics. We'd also like to customize the
<a name="line-148"></a>> -- format of the log message, so we use a 'simpleLogFormatter'
<a name="line-149"></a>>
<a name="line-150"></a>> h <- fileHandler "debug.log" DEBUG >>= \lh -> return $
<a name="line-151"></a>> setFormatter lh (simpleLogFormatter "[$time : $loggername : $prio] $msg")
<a name="line-152"></a>> updateGlobalLogger "MyApp.BuggyComponent" (addHandler h)
<a name="line-153"></a>>
<a name="line-154"></a>> -- This message will go to syslog and stderr,
<a name="line-155"></a>> -- and to the file "debug.log" with a format like :
<a name="line-156"></a>> -- [2010-05-23 16:47:28 : MyApp.BuggyComponent : DEBUG] Some useful diagnostics...
<a name="line-157"></a>> debugM "MyApp.BuggyComponent" "Some useful diagnostics..."
<a name="line-158"></a>>
<a name="line-159"></a>>
<a name="line-160"></a>-}</span>
<a name="line-161"></a>
<a name="line-162"></a><span class='hs-keyword'>module</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Log</span><span class='hs-varop'>.</span><span class='hs-conid'>Logger</span><span class='hs-layout'>(</span>
<a name="line-163"></a> <span class='hs-comment'>-- * Basic Types</span>
<a name="line-164"></a> <span class='hs-conid'>Logger</span><span class='hs-layout'>,</span>
<a name="line-165"></a> <span class='hs-comment'>-- ** Re-Exported from System.Log</span>
<a name="line-166"></a> <span class='hs-conid'>Priority</span><span class='hs-layout'>(</span><span class='hs-keyglyph'>..</span><span class='hs-layout'>)</span><span class='hs-layout'>,</span>
<a name="line-167"></a> <span class='hs-comment'>-- * Logging Messages</span>
<a name="line-168"></a> <span class='hs-comment'>-- ** Basic</span>
<a name="line-169"></a> <span class='hs-varid'>logM</span><span class='hs-layout'>,</span>
<a name="line-170"></a> <span class='hs-comment'>-- ** Utility Functions</span>
<a name="line-171"></a> <span class='hs-comment'>-- These functions are wrappers for 'logM' to</span>
<a name="line-172"></a> <span class='hs-comment'>-- make your job easier.</span>
<a name="line-173"></a> <span class='hs-varid'>debugM</span><span class='hs-layout'>,</span> <span class='hs-varid'>infoM</span><span class='hs-layout'>,</span> <span class='hs-varid'>noticeM</span><span class='hs-layout'>,</span> <span class='hs-varid'>warningM</span><span class='hs-layout'>,</span> <span class='hs-varid'>errorM</span><span class='hs-layout'>,</span>
<a name="line-174"></a> <span class='hs-varid'>criticalM</span><span class='hs-layout'>,</span> <span class='hs-varid'>alertM</span><span class='hs-layout'>,</span> <span class='hs-varid'>emergencyM</span><span class='hs-layout'>,</span>
<a name="line-175"></a> <span class='hs-varid'>traplogging</span><span class='hs-layout'>,</span>
<a name="line-176"></a> <span class='hs-comment'>-- ** Logging to a particular Logger by object</span>
<a name="line-177"></a> <span class='hs-varid'>logL</span><span class='hs-layout'>,</span>
<a name="line-178"></a> <span class='hs-comment'>-- * Logger Manipulation</span>
<a name="line-179"></a><span class='hs-comment'>{- | These functions help you work with loggers. There are some
<a name="line-180"></a>special things to be aware of.
<a name="line-181"></a>
<a name="line-182"></a>First of all, whenever you first access a given logger by name, it
<a name="line-183"></a>magically springs to life. It has a default 'Priority' of Nothing
<a name="line-184"></a>and an empty handler list -- which means that it will inherit whatever its
<a name="line-185"></a>parents do.
<a name="line-186"></a>-}</span>
<a name="line-187"></a> <span class='hs-comment'>-- ** Finding \/ Creating Loggers</span>
<a name="line-188"></a> <span class='hs-varid'>getLogger</span><span class='hs-layout'>,</span> <span class='hs-varid'>getRootLogger</span><span class='hs-layout'>,</span> <span class='hs-varid'>rootLoggerName</span><span class='hs-layout'>,</span>
<a name="line-189"></a> <span class='hs-comment'>-- ** Modifying Loggers</span>
<a name="line-190"></a><span class='hs-comment'>{- | Keep in mind that \"modification\" here is modification in the Haskell
<a name="line-191"></a>sense. We do not actually cause mutation in a specific 'Logger'. Rather,
<a name="line-192"></a>we return you a new 'Logger' object with the change applied.
<a name="line-193"></a>
<a name="line-194"></a>Also, please note that these functions will not have an effect on the
<a name="line-195"></a>global 'Logger' hierarchy. You may use your new 'Logger's locally,
<a name="line-196"></a>but other functions won't see the changes. To make a change global,
<a name="line-197"></a>you'll need to use 'updateGlobalLogger' or 'saveGlobalLogger'.
<a name="line-198"></a>-}</span>
<a name="line-199"></a> <span class='hs-varid'>addHandler</span><span class='hs-layout'>,</span> <span class='hs-varid'>setHandlers</span><span class='hs-layout'>,</span>
<a name="line-200"></a> <span class='hs-varid'>getLevel</span><span class='hs-layout'>,</span> <span class='hs-varid'>setLevel</span><span class='hs-layout'>,</span> <span class='hs-varid'>clearLevel</span><span class='hs-layout'>,</span>
<a name="line-201"></a> <span class='hs-comment'>-- ** Saving Your Changes</span>
<a name="line-202"></a><span class='hs-comment'>{- | These functions commit changes you've made to loggers to the global
<a name="line-203"></a>logger hierarchy. -}</span>
<a name="line-204"></a> <span class='hs-varid'>saveGlobalLogger</span><span class='hs-layout'>,</span>
<a name="line-205"></a> <span class='hs-varid'>updateGlobalLogger</span>
<a name="line-206"></a> <span class='hs-layout'>)</span> <span class='hs-keyword'>where</span>
<a name="line-207"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Log</span>
<a name="line-208"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Log</span><span class='hs-varop'>.</span><span class='hs-conid'>Handler</span><span class='hs-layout'>(</span><span class='hs-conid'>LogHandler</span><span class='hs-layout'>)</span>
<a name="line-209"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Log</span><span class='hs-varop'>.</span><span class='hs-conid'>Formatter</span><span class='hs-layout'>(</span><span class='hs-conid'>LogFormatter</span><span class='hs-layout'>)</span>
<a name="line-210"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Log</span><span class='hs-varop'>.</span><span class='hs-conid'>Handler</span><span class='hs-layout'>(</span><span class='hs-varid'>handle</span><span class='hs-layout'>)</span>
<a name="line-211"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Log</span><span class='hs-varop'>.</span><span class='hs-conid'>Handler</span><span class='hs-varop'>.</span><span class='hs-conid'>Simple</span>
<a name="line-212"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span>
<a name="line-213"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>IO</span><span class='hs-varop'>.</span><span class='hs-conid'>Unsafe</span>
<a name="line-214"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Concurrent</span><span class='hs-varop'>.</span><span class='hs-conid'>MVar</span>
<a name="line-215"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>List</span><span class='hs-layout'>(</span><span class='hs-varid'>map</span><span class='hs-layout'>,</span> <span class='hs-varid'>isPrefixOf</span><span class='hs-layout'>)</span>
<a name="line-216"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Maybe</span>
<a name="line-217"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Data</span><span class='hs-varop'>.</span><span class='hs-conid'>Map</span> <span class='hs-keyword'>as</span> <span class='hs-conid'>Map</span>
<a name="line-218"></a><span class='hs-keyword'>import</span> <span class='hs-keyword'>qualified</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Exception</span>
<a name="line-219"></a><span class='hs-keyword'>import</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Monad</span><span class='hs-varop'>.</span><span class='hs-conid'>Error</span>
<a name="line-220"></a><a name="HandlerT"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-221"></a><a name="HandlerT"></a><span class='hs-comment'>-- Basic logger types</span>
<a name="line-222"></a><a name="HandlerT"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-223"></a><a name="HandlerT"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>HandlerT</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>forall</span> <span class='hs-varid'>a</span><span class='hs-varop'>.</span> <span class='hs-conid'>LogHandler</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-conid'>HandlerT</span> <span class='hs-varid'>a</span>
<a name="line-224"></a>
<a name="line-225"></a><a name="Logger"></a><span class='hs-keyword'>data</span> <span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Logger</span> <span class='hs-layout'>{</span> <span class='hs-varid'>level</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Maybe</span> <span class='hs-conid'>Priority</span><span class='hs-layout'>,</span>
<a name="line-226"></a> <span class='hs-varid'>handlers</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>HandlerT</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>,</span>
<a name="line-227"></a> <span class='hs-varid'>name</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span><span class='hs-layout'>}</span>
<a name="line-228"></a>
<a name="line-229"></a><a name="LogTree"></a><span class='hs-keyword'>type</span> <span class='hs-conid'>LogTree</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Map</span><span class='hs-varop'>.</span><span class='hs-conid'>Map</span> <span class='hs-conid'>String</span> <span class='hs-conid'>Logger</span>
<a name="line-230"></a>
<a name="line-231"></a><span class='hs-comment'>{- | This is the base class for the various log handlers. They should
<a name="line-232"></a>all adhere to this class. -}</span>
<a name="line-233"></a>
<a name="line-234"></a>
<a name="line-235"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-236"></a><span class='hs-comment'>-- Utilities</span>
<a name="line-237"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-238"></a>
<a name="line-239"></a><a name="rootLoggerName"></a><span class='hs-comment'>-- | The name of the root logger, which is always defined and present</span>
<a name="line-240"></a><span class='hs-comment'>-- on the system.</span>
<a name="line-241"></a><span class='hs-definition'>rootLoggerName</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span>
<a name="line-242"></a><span class='hs-definition'>rootLoggerName</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>""</span>
<a name="line-243"></a>
<a name="line-244"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-245"></a><span class='hs-comment'>-- Logger Tree Storage</span>
<a name="line-246"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-247"></a>
<a name="line-248"></a><span class='hs-comment'>-- | The log tree. Initialize it with a default root logger </span>
<a name="line-249"></a><span class='hs-comment'>-- and (FIXME) a logger for MissingH itself.</span>
<a name="line-250"></a>
<a name="line-251"></a><span class='hs-comment'>{-# NOINLINE logTree #-}</span>
<a name="line-252"></a>
<a name="line-253"></a><a name="logTree"></a><span class='hs-definition'>logTree</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>MVar</span> <span class='hs-conid'>LogTree</span>
<a name="line-254"></a><span class='hs-comment'>-- note: only kick up tree if handled locally</span>
<a name="line-255"></a><span class='hs-definition'>logTree</span> <span class='hs-keyglyph'>=</span>
<a name="line-256"></a> <span class='hs-varid'>unsafePerformIO</span> <span class='hs-varop'>$</span> <span class='hs-keyword'>do</span>
<a name="line-257"></a> <span class='hs-varid'>h</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>streamHandler</span> <span class='hs-varid'>stderr</span> <span class='hs-conid'>DEBUG</span>
<a name="line-258"></a> <span class='hs-varid'>newMVar</span> <span class='hs-layout'>(</span><span class='hs-conid'>Map</span><span class='hs-varop'>.</span><span class='hs-varid'>singleton</span> <span class='hs-varid'>rootLoggerName</span> <span class='hs-layout'>(</span><span class='hs-conid'>Logger</span>
<a name="line-259"></a> <span class='hs-layout'>{</span><span class='hs-varid'>level</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-conid'>WARNING</span><span class='hs-layout'>,</span>
<a name="line-260"></a> <span class='hs-varid'>name</span> <span class='hs-keyglyph'>=</span> <span class='hs-str'>""</span><span class='hs-layout'>,</span>
<a name="line-261"></a> <span class='hs-varid'>handlers</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>HandlerT</span> <span class='hs-varid'>h</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>}</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-262"></a>
<a name="line-263"></a><a name="componentsOfName"></a><span class='hs-comment'>{- | Given a name, return all components of it, starting from the root.
<a name="line-264"></a>Example return value:
<a name="line-265"></a>
<a name="line-266"></a>>["", "MissingH", "System.Cmd.Utils", "System.Cmd.Utils.pOpen"]
<a name="line-267"></a>
<a name="line-268"></a>-}</span>
<a name="line-269"></a><span class='hs-definition'>componentsOfName</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>String</span><span class='hs-keyglyph'>]</span>
<a name="line-270"></a><span class='hs-definition'>componentsOfName</span> <span class='hs-varid'>name</span> <span class='hs-keyglyph'>=</span>
<a name="line-271"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>joinComp</span> <span class='hs-conid'>[]</span> <span class='hs-keyword'>_</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>[]</span>
<a name="line-272"></a> <span class='hs-varid'>joinComp</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>x</span> <span class='hs-conop'>:</span> <span class='hs-varid'>joinComp</span> <span class='hs-varid'>xs</span> <span class='hs-varid'>x</span>
<a name="line-273"></a> <span class='hs-varid'>joinComp</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-varid'>accum</span> <span class='hs-keyglyph'>=</span>
<a name="line-274"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>newlevel</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>accum</span> <span class='hs-varop'>++</span> <span class='hs-str'>"."</span> <span class='hs-varop'>++</span> <span class='hs-varid'>x</span> <span class='hs-keyword'>in</span>
<a name="line-275"></a> <span class='hs-varid'>newlevel</span> <span class='hs-conop'>:</span> <span class='hs-varid'>joinComp</span> <span class='hs-varid'>xs</span> <span class='hs-varid'>newlevel</span>
<a name="line-276"></a> <span class='hs-keyword'>in</span>
<a name="line-277"></a> <span class='hs-varid'>rootLoggerName</span> <span class='hs-conop'>:</span> <span class='hs-varid'>joinComp</span> <span class='hs-layout'>(</span><span class='hs-varid'>split</span> <span class='hs-str'>"."</span> <span class='hs-varid'>name</span><span class='hs-layout'>)</span> <span class='hs-conid'>[]</span>
<a name="line-278"></a>
<a name="line-279"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-280"></a><span class='hs-comment'>-- Logging With Location</span>
<a name="line-281"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-282"></a>
<a name="line-283"></a><span class='hs-comment'>{- | Log a message using the given logger at a given priority. -}</span>
<a name="line-284"></a>
<a name="line-285"></a><a name="logM"></a><span class='hs-definition'>logM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Name of the logger to use</span>
<a name="line-286"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Priority</span> <span class='hs-comment'>-- ^ Priority of this message</span>
<a name="line-287"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ The log text itself</span>
<a name="line-288"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-289"></a>
<a name="line-290"></a><span class='hs-definition'>logM</span> <span class='hs-varid'>logname</span> <span class='hs-varid'>pri</span> <span class='hs-varid'>msg</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-291"></a> <span class='hs-varid'>l</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>getLogger</span> <span class='hs-varid'>logname</span>
<a name="line-292"></a> <span class='hs-varid'>logL</span> <span class='hs-varid'>l</span> <span class='hs-varid'>pri</span> <span class='hs-varid'>msg</span>
<a name="line-293"></a>
<a name="line-294"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-295"></a><span class='hs-comment'>-- Utility functions</span>
<a name="line-296"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-297"></a>
<a name="line-298"></a><a name="debugM"></a><span class='hs-comment'>{- | Log a message at 'DEBUG' priority -}</span>
<a name="line-299"></a><span class='hs-definition'>debugM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Logger name</span>
<a name="line-300"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Log message</span>
<a name="line-301"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-302"></a><span class='hs-definition'>debugM</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>logM</span> <span class='hs-varid'>s</span> <span class='hs-conid'>DEBUG</span>
<a name="line-303"></a>
<a name="line-304"></a><a name="infoM"></a><span class='hs-comment'>{- | Log a message at 'INFO' priority -}</span>
<a name="line-305"></a><span class='hs-definition'>infoM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Logger name</span>
<a name="line-306"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Log message</span>
<a name="line-307"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-308"></a><span class='hs-definition'>infoM</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>logM</span> <span class='hs-varid'>s</span> <span class='hs-conid'>INFO</span>
<a name="line-309"></a>
<a name="line-310"></a><a name="noticeM"></a><span class='hs-comment'>{- | Log a message at 'NOTICE' priority -}</span>
<a name="line-311"></a><span class='hs-definition'>noticeM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Logger name</span>
<a name="line-312"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Log message</span>
<a name="line-313"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-314"></a><span class='hs-definition'>noticeM</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>logM</span> <span class='hs-varid'>s</span> <span class='hs-conid'>NOTICE</span>
<a name="line-315"></a>
<a name="line-316"></a><a name="warningM"></a><span class='hs-comment'>{- | Log a message at 'WARNING' priority -}</span>
<a name="line-317"></a><span class='hs-definition'>warningM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Logger name</span>
<a name="line-318"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Log message</span>
<a name="line-319"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-320"></a><span class='hs-definition'>warningM</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>logM</span> <span class='hs-varid'>s</span> <span class='hs-conid'>WARNING</span>
<a name="line-321"></a>
<a name="line-322"></a><a name="errorM"></a><span class='hs-comment'>{- | Log a message at 'ERROR' priority -}</span>
<a name="line-323"></a><span class='hs-definition'>errorM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Logger name</span>
<a name="line-324"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Log message</span>
<a name="line-325"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-326"></a><span class='hs-definition'>errorM</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>logM</span> <span class='hs-varid'>s</span> <span class='hs-conid'>ERROR</span>
<a name="line-327"></a>
<a name="line-328"></a><a name="criticalM"></a><span class='hs-comment'>{- | Log a message at 'CRITICAL' priority -}</span>
<a name="line-329"></a><span class='hs-definition'>criticalM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Logger name</span>
<a name="line-330"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Log message</span>
<a name="line-331"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-332"></a><span class='hs-definition'>criticalM</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>logM</span> <span class='hs-varid'>s</span> <span class='hs-conid'>CRITICAL</span>
<a name="line-333"></a>
<a name="line-334"></a><a name="alertM"></a><span class='hs-comment'>{- | Log a message at 'ALERT' priority -}</span>
<a name="line-335"></a><span class='hs-definition'>alertM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Logger name</span>
<a name="line-336"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Log message</span>
<a name="line-337"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-338"></a><span class='hs-definition'>alertM</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>logM</span> <span class='hs-varid'>s</span> <span class='hs-conid'>ALERT</span>
<a name="line-339"></a>
<a name="line-340"></a><a name="emergencyM"></a><span class='hs-comment'>{- | Log a message at 'EMERGENCY' priority -}</span>
<a name="line-341"></a><span class='hs-definition'>emergencyM</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Logger name</span>
<a name="line-342"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Log message</span>
<a name="line-343"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-344"></a><span class='hs-definition'>emergencyM</span> <span class='hs-varid'>s</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>logM</span> <span class='hs-varid'>s</span> <span class='hs-conid'>EMERGENCY</span>
<a name="line-345"></a>
<a name="line-346"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-347"></a><span class='hs-comment'>-- Public Logger Interaction Support</span>
<a name="line-348"></a><span class='hs-comment'>---------------------------------------------------------------------------</span>
<a name="line-349"></a>
<a name="line-350"></a><span class='hs-comment'>-- | Returns the logger for the given name. If no logger with that name</span>
<a name="line-351"></a><span class='hs-comment'>-- exists, creates new loggers and any necessary parent loggers, with</span>
<a name="line-352"></a><span class='hs-comment'>-- no connected handlers.</span>
<a name="line-353"></a>
<a name="line-354"></a><a name="getLogger"></a><span class='hs-definition'>getLogger</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Logger</span>
<a name="line-355"></a><span class='hs-definition'>getLogger</span> <span class='hs-varid'>lname</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>modifyMVar</span> <span class='hs-varid'>logTree</span> <span class='hs-varop'>$</span> <span class='hs-keyglyph'>\</span><span class='hs-varid'>lt</span> <span class='hs-keyglyph'>-></span>
<a name="line-356"></a> <span class='hs-keyword'>case</span> <span class='hs-conid'>Map</span><span class='hs-varop'>.</span><span class='hs-varid'>lookup</span> <span class='hs-varid'>lname</span> <span class='hs-varid'>lt</span> <span class='hs-keyword'>of</span>
<a name="line-357"></a> <span class='hs-conid'>Just</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>lt</span><span class='hs-layout'>,</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span> <span class='hs-comment'>-- A logger exists; return it and leave tree</span>
<a name="line-358"></a> <span class='hs-conid'>Nothing</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>do</span>
<a name="line-359"></a> <span class='hs-comment'>-- Add logger(s). Then call myself to retrieve it.</span>
<a name="line-360"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>newlt</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>createLoggers</span> <span class='hs-layout'>(</span><span class='hs-varid'>componentsOfName</span> <span class='hs-varid'>lname</span><span class='hs-layout'>)</span> <span class='hs-varid'>lt</span>
<a name="line-361"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>result</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>fromJust</span> <span class='hs-varop'>$</span> <span class='hs-conid'>Map</span><span class='hs-varop'>.</span><span class='hs-varid'>lookup</span> <span class='hs-varid'>lname</span> <span class='hs-varid'>newlt</span>
<a name="line-362"></a> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>newlt</span><span class='hs-layout'>,</span> <span class='hs-varid'>result</span><span class='hs-layout'>)</span>
<a name="line-363"></a> <span class='hs-keyword'>where</span> <span class='hs-varid'>createLoggers</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>String</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>LogTree</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>LogTree</span>
<a name="line-364"></a> <span class='hs-varid'>createLoggers</span> <span class='hs-conid'>[]</span> <span class='hs-varid'>lt</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>lt</span> <span class='hs-comment'>-- No names to add; return tree unmodified</span>
<a name="line-365"></a> <span class='hs-varid'>createLoggers</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-varid'>lt</span> <span class='hs-keyglyph'>=</span> <span class='hs-comment'>-- Add logger to tree</span>
<a name="line-366"></a> <span class='hs-keyword'>if</span> <span class='hs-conid'>Map</span><span class='hs-varop'>.</span><span class='hs-varid'>member</span> <span class='hs-varid'>x</span> <span class='hs-varid'>lt</span>
<a name="line-367"></a> <span class='hs-keyword'>then</span> <span class='hs-varid'>createLoggers</span> <span class='hs-varid'>xs</span> <span class='hs-varid'>lt</span>
<a name="line-368"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>createLoggers</span> <span class='hs-varid'>xs</span>
<a name="line-369"></a> <span class='hs-layout'>(</span><span class='hs-conid'>Map</span><span class='hs-varop'>.</span><span class='hs-varid'>insert</span> <span class='hs-varid'>x</span> <span class='hs-layout'>(</span><span class='hs-varid'>defaultLogger</span> <span class='hs-layout'>{</span><span class='hs-varid'>name</span><span class='hs-keyglyph'>=</span><span class='hs-varid'>x</span><span class='hs-layout'>}</span><span class='hs-layout'>)</span> <span class='hs-varid'>lt</span><span class='hs-layout'>)</span>
<a name="line-370"></a> <span class='hs-varid'>defaultLogger</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Logger</span> <span class='hs-conid'>Nothing</span> <span class='hs-conid'>[]</span> <span class='hs-varid'>undefined</span>
<a name="line-371"></a>
<a name="line-372"></a><span class='hs-comment'>-- | Returns the root logger.</span>
<a name="line-373"></a>
<a name="line-374"></a><a name="getRootLogger"></a><span class='hs-definition'>getRootLogger</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Logger</span>
<a name="line-375"></a><span class='hs-definition'>getRootLogger</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>getLogger</span> <span class='hs-varid'>rootLoggerName</span>
<a name="line-376"></a>
<a name="line-377"></a><a name="logL"></a><span class='hs-comment'>-- | Log a message, assuming the current logger's level permits it.</span>
<a name="line-378"></a><span class='hs-definition'>logL</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Priority</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-379"></a><span class='hs-definition'>logL</span> <span class='hs-varid'>l</span> <span class='hs-varid'>pri</span> <span class='hs-varid'>msg</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>handle</span> <span class='hs-varid'>l</span> <span class='hs-layout'>(</span><span class='hs-varid'>pri</span><span class='hs-layout'>,</span> <span class='hs-varid'>msg</span><span class='hs-layout'>)</span>
<a name="line-380"></a>
<a name="line-381"></a><a name="handle"></a><span class='hs-comment'>-- | Handle a log request.</span>
<a name="line-382"></a><span class='hs-definition'>handle</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>LogRecord</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-383"></a><span class='hs-definition'>handle</span> <span class='hs-varid'>l</span> <span class='hs-layout'>(</span><span class='hs-varid'>pri</span><span class='hs-layout'>,</span> <span class='hs-varid'>msg</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span>
<a name="line-384"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>parentLoggers</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>Logger</span><span class='hs-keyglyph'>]</span>
<a name="line-385"></a> <span class='hs-varid'>parentLoggers</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>return</span> <span class='hs-conid'>[]</span>
<a name="line-386"></a> <span class='hs-varid'>parentLoggers</span> <span class='hs-varid'>name</span> <span class='hs-keyglyph'>=</span>
<a name="line-387"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>pname</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-varid'>head</span> <span class='hs-varop'>.</span> <span class='hs-varid'>drop</span> <span class='hs-num'>1</span> <span class='hs-varop'>.</span> <span class='hs-varid'>reverse</span> <span class='hs-varop'>.</span> <span class='hs-varid'>componentsOfName</span><span class='hs-layout'>)</span> <span class='hs-varid'>name</span>
<a name="line-388"></a> <span class='hs-keyword'>in</span>
<a name="line-389"></a> <span class='hs-keyword'>do</span> <span class='hs-varid'>parent</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>getLogger</span> <span class='hs-varid'>pname</span>
<a name="line-390"></a> <span class='hs-varid'>next</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>parentLoggers</span> <span class='hs-varid'>pname</span>
<a name="line-391"></a> <span class='hs-varid'>return</span> <span class='hs-layout'>(</span><span class='hs-varid'>parent</span> <span class='hs-conop'>:</span> <span class='hs-varid'>next</span><span class='hs-layout'>)</span>
<a name="line-392"></a> <span class='hs-varid'>parentHandlers</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>HandlerT</span><span class='hs-keyglyph'>]</span>
<a name="line-393"></a> <span class='hs-varid'>parentHandlers</span> <span class='hs-varid'>name</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>parentLoggers</span> <span class='hs-varid'>name</span> <span class='hs-varop'>>>=</span> <span class='hs-layout'>(</span><span class='hs-varid'>return</span> <span class='hs-varop'>.</span> <span class='hs-varid'>concatMap</span> <span class='hs-varid'>handlers</span><span class='hs-layout'>)</span>
<a name="line-394"></a>
<a name="line-395"></a> <span class='hs-comment'>-- Get the priority we should use. Find the first logger in the tree,</span>
<a name="line-396"></a> <span class='hs-comment'>-- starting here, with a set priority. If even root doesn't have one,</span>
<a name="line-397"></a> <span class='hs-comment'>-- assume DEBUG.</span>
<a name="line-398"></a> <span class='hs-varid'>getLoggerPriority</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>Priority</span>
<a name="line-399"></a> <span class='hs-varid'>getLoggerPriority</span> <span class='hs-varid'>name</span> <span class='hs-keyglyph'>=</span>
<a name="line-400"></a> <span class='hs-keyword'>do</span> <span class='hs-varid'>pl</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>parentLoggers</span> <span class='hs-varid'>name</span>
<a name="line-401"></a> <span class='hs-keyword'>case</span> <span class='hs-varid'>catMaybes</span> <span class='hs-varop'>.</span> <span class='hs-varid'>map</span> <span class='hs-varid'>level</span> <span class='hs-varop'>$</span> <span class='hs-layout'>(</span><span class='hs-varid'>l</span> <span class='hs-conop'>:</span> <span class='hs-varid'>pl</span><span class='hs-layout'>)</span> <span class='hs-keyword'>of</span>
<a name="line-402"></a> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>return</span> <span class='hs-conid'>DEBUG</span>
<a name="line-403"></a> <span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-keyword'>_</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>return</span> <span class='hs-varid'>x</span>
<a name="line-404"></a> <span class='hs-keyword'>in</span>
<a name="line-405"></a> <span class='hs-keyword'>do</span> <span class='hs-varid'>lp</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>getLoggerPriority</span> <span class='hs-layout'>(</span><span class='hs-varid'>name</span> <span class='hs-varid'>l</span><span class='hs-layout'>)</span>
<a name="line-406"></a> <span class='hs-keyword'>if</span> <span class='hs-varid'>pri</span> <span class='hs-varop'>>=</span> <span class='hs-varid'>lp</span>
<a name="line-407"></a> <span class='hs-keyword'>then</span> <span class='hs-keyword'>do</span>
<a name="line-408"></a> <span class='hs-varid'>ph</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>parentHandlers</span> <span class='hs-layout'>(</span><span class='hs-varid'>name</span> <span class='hs-varid'>l</span><span class='hs-layout'>)</span>
<a name="line-409"></a> <span class='hs-varid'>sequence_</span> <span class='hs-layout'>(</span><span class='hs-varid'>handlerActions</span> <span class='hs-layout'>(</span><span class='hs-varid'>ph</span> <span class='hs-varop'>++</span> <span class='hs-layout'>(</span><span class='hs-varid'>handlers</span> <span class='hs-varid'>l</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span> <span class='hs-layout'>(</span><span class='hs-varid'>pri</span><span class='hs-layout'>,</span> <span class='hs-varid'>msg</span><span class='hs-layout'>)</span>
<a name="line-410"></a> <span class='hs-layout'>(</span><span class='hs-varid'>name</span> <span class='hs-varid'>l</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-411"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>return</span> <span class='hs-conid'>()</span>
<a name="line-412"></a>
<a name="line-413"></a><a name="callHandler"></a><span class='hs-comment'>-- | Call a handler given a HandlerT.</span>
<a name="line-414"></a><span class='hs-definition'>callHandler</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>LogRecord</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>HandlerT</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-415"></a><span class='hs-definition'>callHandler</span> <span class='hs-varid'>lr</span> <span class='hs-varid'>loggername</span> <span class='hs-varid'>ht</span> <span class='hs-keyglyph'>=</span>
<a name="line-416"></a> <span class='hs-keyword'>case</span> <span class='hs-varid'>ht</span> <span class='hs-keyword'>of</span>
<a name="line-417"></a> <span class='hs-conid'>HandlerT</span> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>System</span><span class='hs-varop'>.</span><span class='hs-conid'>Log</span><span class='hs-varop'>.</span><span class='hs-conid'>Handler</span><span class='hs-varop'>.</span><span class='hs-varid'>handle</span> <span class='hs-varid'>x</span> <span class='hs-varid'>lr</span> <span class='hs-varid'>loggername</span>
<a name="line-418"></a>
<a name="line-419"></a><a name="handlerActions"></a><span class='hs-comment'>-- | Generate IO actions for the handlers.</span>
<a name="line-420"></a><span class='hs-definition'>handlerActions</span> <span class='hs-keyglyph'>::</span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>HandlerT</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>LogRecord</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-conid'>IO</span> <span class='hs-conid'>()</span><span class='hs-keyglyph'>]</span>
<a name="line-421"></a><span class='hs-definition'>handlerActions</span> <span class='hs-varid'>h</span> <span class='hs-varid'>lr</span> <span class='hs-varid'>loggername</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>map</span> <span class='hs-layout'>(</span><span class='hs-varid'>callHandler</span> <span class='hs-varid'>lr</span> <span class='hs-varid'>loggername</span> <span class='hs-layout'>)</span> <span class='hs-varid'>h</span>
<a name="line-422"></a>
<a name="line-423"></a><a name="addHandler"></a><span class='hs-comment'>-- | Add handler to 'Logger'. Returns a new 'Logger'.</span>
<a name="line-424"></a><span class='hs-definition'>addHandler</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>LogHandler</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Logger</span>
<a name="line-425"></a><span class='hs-definition'>addHandler</span> <span class='hs-varid'>h</span> <span class='hs-varid'>l</span><span class='hs-keyglyph'>=</span> <span class='hs-varid'>l</span><span class='hs-layout'>{</span><span class='hs-varid'>handlers</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-conid'>HandlerT</span> <span class='hs-varid'>h</span><span class='hs-layout'>)</span> <span class='hs-conop'>:</span> <span class='hs-layout'>(</span><span class='hs-varid'>handlers</span> <span class='hs-varid'>l</span><span class='hs-layout'>)</span><span class='hs-layout'>}</span>
<a name="line-426"></a>
<a name="line-427"></a><a name="setHandlers"></a><span class='hs-comment'>-- | Set the 'Logger'\'s list of handlers to the list supplied.</span>
<a name="line-428"></a><span class='hs-comment'>-- All existing handlers are removed first.</span>
<a name="line-429"></a><span class='hs-definition'>setHandlers</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>LogHandler</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Logger</span>
<a name="line-430"></a><span class='hs-definition'>setHandlers</span> <span class='hs-varid'>hl</span> <span class='hs-varid'>l</span> <span class='hs-keyglyph'>=</span>
<a name="line-431"></a> <span class='hs-varid'>l</span><span class='hs-layout'>{</span><span class='hs-varid'>handlers</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>map</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>h</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>HandlerT</span> <span class='hs-varid'>h</span><span class='hs-layout'>)</span> <span class='hs-varid'>hl</span><span class='hs-layout'>}</span>
<a name="line-432"></a>
<a name="line-433"></a><span class='hs-comment'>-- | Returns the "level" of the logger. Items beneath this</span>
<a name="line-434"></a><span class='hs-comment'>-- level will be ignored.</span>
<a name="line-435"></a>
<a name="line-436"></a><a name="getLevel"></a><span class='hs-definition'>getLevel</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Maybe</span> <span class='hs-conid'>Priority</span>
<a name="line-437"></a><span class='hs-definition'>getLevel</span> <span class='hs-varid'>l</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>level</span> <span class='hs-varid'>l</span>
<a name="line-438"></a>
<a name="line-439"></a><span class='hs-comment'>-- | Sets the "level" of the 'Logger'. Returns a new</span>
<a name="line-440"></a><span class='hs-comment'>-- 'Logger' object with the new level.</span>
<a name="line-441"></a>
<a name="line-442"></a><a name="setLevel"></a><span class='hs-definition'>setLevel</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Priority</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Logger</span>
<a name="line-443"></a><span class='hs-definition'>setLevel</span> <span class='hs-varid'>p</span> <span class='hs-varid'>l</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>l</span><span class='hs-layout'>{</span><span class='hs-varid'>level</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Just</span> <span class='hs-varid'>p</span><span class='hs-layout'>}</span>
<a name="line-444"></a>
<a name="line-445"></a><span class='hs-comment'>-- | Clears the "level" of the 'Logger'. It will now inherit the level of</span>
<a name="line-446"></a><span class='hs-comment'>-- | its parent.</span>
<a name="line-447"></a>
<a name="line-448"></a><a name="clearLevel"></a><span class='hs-definition'>clearLevel</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Logger</span>
<a name="line-449"></a><span class='hs-definition'>clearLevel</span> <span class='hs-varid'>l</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>l</span> <span class='hs-layout'>{</span><span class='hs-varid'>level</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>Nothing</span><span class='hs-layout'>}</span>
<a name="line-450"></a>
<a name="line-451"></a><span class='hs-comment'>-- | Updates the global record for the given logger to take into</span>
<a name="line-452"></a><span class='hs-comment'>-- account any changes you may have made.</span>
<a name="line-453"></a>
<a name="line-454"></a><a name="saveGlobalLogger"></a><span class='hs-definition'>saveGlobalLogger</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-455"></a><span class='hs-definition'>saveGlobalLogger</span> <span class='hs-varid'>l</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>modifyMVar_</span> <span class='hs-varid'>logTree</span>
<a name="line-456"></a> <span class='hs-layout'>(</span><span class='hs-keyglyph'>\</span><span class='hs-varid'>lt</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>return</span> <span class='hs-varop'>$</span> <span class='hs-conid'>Map</span><span class='hs-varop'>.</span><span class='hs-varid'>insert</span> <span class='hs-layout'>(</span><span class='hs-varid'>name</span> <span class='hs-varid'>l</span><span class='hs-layout'>)</span> <span class='hs-varid'>l</span> <span class='hs-varid'>lt</span><span class='hs-layout'>)</span>
<a name="line-457"></a>
<a name="line-458"></a><span class='hs-comment'>{- | Helps you make changes on the given logger. Takes a function
<a name="line-459"></a>that makes changes and writes those changes back to the global
<a name="line-460"></a>database. Here's an example from above (\"s\" is a 'LogHandler'):
<a name="line-461"></a>
<a name="line-462"></a>> updateGlobalLogger "MyApp.BuggyComponent"
<a name="line-463"></a>> (setLevel DEBUG . setHandlers [s])
<a name="line-464"></a>-}</span>
<a name="line-465"></a>
<a name="line-466"></a><a name="updateGlobalLogger"></a><span class='hs-definition'>updateGlobalLogger</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- ^ Logger name</span>
<a name="line-467"></a> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-conid'>Logger</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Logger</span><span class='hs-layout'>)</span> <span class='hs-comment'>-- ^ Function to call</span>
<a name="line-468"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-conid'>()</span>
<a name="line-469"></a><span class='hs-definition'>updateGlobalLogger</span> <span class='hs-varid'>ln</span> <span class='hs-varid'>func</span> <span class='hs-keyglyph'>=</span>
<a name="line-470"></a> <span class='hs-keyword'>do</span> <span class='hs-varid'>l</span> <span class='hs-keyglyph'><-</span> <span class='hs-varid'>getLogger</span> <span class='hs-varid'>ln</span>
<a name="line-471"></a> <span class='hs-varid'>saveGlobalLogger</span> <span class='hs-layout'>(</span><span class='hs-varid'>func</span> <span class='hs-varid'>l</span><span class='hs-layout'>)</span>
<a name="line-472"></a>
<a name="line-473"></a><span class='hs-comment'>{- | Traps exceptions that may occur, logging them, then passing them on.
<a name="line-474"></a>
<a name="line-475"></a>Takes a logger name, priority, leading description text (you can set it to
<a name="line-476"></a>@\"\"@ if you don't want any), and action to run.
<a name="line-477"></a>-}</span>
<a name="line-478"></a>
<a name="line-479"></a><a name="traplogging"></a><span class='hs-definition'>traplogging</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- Logger name</span>
<a name="line-480"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Priority</span> <span class='hs-comment'>-- Logging priority</span>
<a name="line-481"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>String</span> <span class='hs-comment'>-- Descriptive text to prepend to logged messages</span>
<a name="line-482"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-varid'>a</span> <span class='hs-comment'>-- Action to run</span>
<a name="line-483"></a> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-varid'>a</span> <span class='hs-comment'>-- Return value</span>
<a name="line-484"></a><span class='hs-definition'>traplogging</span> <span class='hs-varid'>logger</span> <span class='hs-varid'>priority</span> <span class='hs-varid'>desc</span> <span class='hs-varid'>action</span> <span class='hs-keyglyph'>=</span>
<a name="line-485"></a> <span class='hs-keyword'>let</span> <span class='hs-varid'>realdesc</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>desc</span> <span class='hs-keyword'>of</span>
<a name="line-486"></a> <span class='hs-str'>""</span> <span class='hs-keyglyph'>-></span> <span class='hs-str'>""</span>
<a name="line-487"></a> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>-></span> <span class='hs-varid'>x</span> <span class='hs-varop'>++</span> <span class='hs-str'>": "</span>
<a name="line-488"></a> <span class='hs-varid'>handler</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Exception</span><span class='hs-varop'>.</span><span class='hs-conid'>SomeException</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>IO</span> <span class='hs-varid'>a</span>
<a name="line-489"></a> <span class='hs-varid'>handler</span> <span class='hs-varid'>e</span> <span class='hs-keyglyph'>=</span> <span class='hs-keyword'>do</span>
<a name="line-490"></a> <span class='hs-varid'>logM</span> <span class='hs-varid'>logger</span> <span class='hs-varid'>priority</span> <span class='hs-layout'>(</span><span class='hs-varid'>realdesc</span> <span class='hs-varop'>++</span> <span class='hs-layout'>(</span><span class='hs-varid'>show</span> <span class='hs-varid'>e</span><span class='hs-layout'>)</span><span class='hs-layout'>)</span>
<a name="line-491"></a> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Exception</span><span class='hs-varop'>.</span><span class='hs-varid'>throw</span> <span class='hs-varid'>e</span> <span class='hs-comment'>-- Re-raise it</span>
<a name="line-492"></a> <span class='hs-keyword'>in</span>
<a name="line-493"></a> <span class='hs-conid'>Control</span><span class='hs-varop'>.</span><span class='hs-conid'>Exception</span><span class='hs-varop'>.</span><span class='hs-varid'>catch</span> <span class='hs-varid'>action</span> <span class='hs-varid'>handler</span>
<a name="line-494"></a>
<a name="line-495"></a><a name="split"></a><span class='hs-comment'>{- This function pulled in from MissingH to avoid a dep on it -}</span>
<a name="line-496"></a><span class='hs-definition'>split</span> <span class='hs-keyglyph'>::</span> <span class='hs-conid'>Eq</span> <span class='hs-varid'>a</span> <span class='hs-keyglyph'>=></span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span><span class='hs-keyglyph'>]</span>
<a name="line-497"></a><span class='hs-definition'>split</span> <span class='hs-keyword'>_</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-conid'>[]</span>
<a name="line-498"></a><span class='hs-definition'>split</span> <span class='hs-varid'>delim</span> <span class='hs-varid'>str</span> <span class='hs-keyglyph'>=</span>
<a name="line-499"></a> <span class='hs-keyword'>let</span> <span class='hs-layout'>(</span><span class='hs-varid'>firstline</span><span class='hs-layout'>,</span> <span class='hs-varid'>remainder</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>breakList</span> <span class='hs-layout'>(</span><span class='hs-varid'>isPrefixOf</span> <span class='hs-varid'>delim</span><span class='hs-layout'>)</span> <span class='hs-varid'>str</span>
<a name="line-500"></a> <span class='hs-keyword'>in</span>
<a name="line-501"></a> <span class='hs-varid'>firstline</span> <span class='hs-conop'>:</span> <span class='hs-keyword'>case</span> <span class='hs-varid'>remainder</span> <span class='hs-keyword'>of</span>
<a name="line-502"></a> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>[]</span>
<a name="line-503"></a> <span class='hs-varid'>x</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyword'>if</span> <span class='hs-varid'>x</span> <span class='hs-varop'>==</span> <span class='hs-varid'>delim</span>
<a name="line-504"></a> <span class='hs-keyword'>then</span> <span class='hs-conid'>[]</span> <span class='hs-conop'>:</span> <span class='hs-conid'>[]</span>
<a name="line-505"></a> <span class='hs-keyword'>else</span> <span class='hs-varid'>split</span> <span class='hs-varid'>delim</span>
<a name="line-506"></a> <span class='hs-layout'>(</span><span class='hs-varid'>drop</span> <span class='hs-layout'>(</span><span class='hs-varid'>length</span> <span class='hs-varid'>delim</span><span class='hs-layout'>)</span> <span class='hs-varid'>x</span><span class='hs-layout'>)</span>
<a name="line-507"></a>
<a name="line-508"></a><a name="breakList"></a><span class='hs-comment'>-- This function also pulled from MissingH</span>
<a name="line-509"></a><span class='hs-definition'>breakList</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>,</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span>
<a name="line-510"></a><span class='hs-definition'>breakList</span> <span class='hs-varid'>func</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>spanList</span> <span class='hs-layout'>(</span><span class='hs-varid'>not</span> <span class='hs-varop'>.</span> <span class='hs-varid'>func</span><span class='hs-layout'>)</span>
<a name="line-511"></a>
<a name="line-512"></a><a name="spanList"></a><span class='hs-comment'>-- This function also pulled from MissingH</span>
<a name="line-513"></a><span class='hs-definition'>spanList</span> <span class='hs-keyglyph'>::</span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-conid'>Bool</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>-></span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span> <span class='hs-keyglyph'>-></span> <span class='hs-layout'>(</span><span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>,</span> <span class='hs-keyglyph'>[</span><span class='hs-varid'>a</span><span class='hs-keyglyph'>]</span><span class='hs-layout'>)</span>
<a name="line-514"></a>
<a name="line-515"></a><span class='hs-definition'>spanList</span> <span class='hs-keyword'>_</span> <span class='hs-conid'>[]</span> <span class='hs-keyglyph'>=</span> <span class='hs-layout'>(</span><span class='hs-conid'>[]</span><span class='hs-layout'>,</span><span class='hs-conid'>[]</span><span class='hs-layout'>)</span>
<a name="line-516"></a><span class='hs-definition'>spanList</span> <span class='hs-varid'>func</span> <span class='hs-varid'>list</span><span class='hs-keyglyph'>@</span><span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-varid'>xs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span>
<a name="line-517"></a> <span class='hs-keyword'>if</span> <span class='hs-varid'>func</span> <span class='hs-varid'>list</span>
<a name="line-518"></a> <span class='hs-keyword'>then</span> <span class='hs-layout'>(</span><span class='hs-varid'>x</span><span class='hs-conop'>:</span><span class='hs-varid'>ys</span><span class='hs-layout'>,</span><span class='hs-varid'>zs</span><span class='hs-layout'>)</span>
<a name="line-519"></a> <span class='hs-keyword'>else</span> <span class='hs-layout'>(</span><span class='hs-conid'>[]</span><span class='hs-layout'>,</span><span class='hs-varid'>list</span><span class='hs-layout'>)</span>
<a name="line-520"></a> <span class='hs-keyword'>where</span> <span class='hs-layout'>(</span><span class='hs-varid'>ys</span><span class='hs-layout'>,</span><span class='hs-varid'>zs</span><span class='hs-layout'>)</span> <span class='hs-keyglyph'>=</span> <span class='hs-varid'>spanList</span> <span class='hs-varid'>func</span> <span class='hs-varid'>xs</span>
<a name="line-521"></a>
</pre></body>
</html>
