<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>Language.Haskell.Pretty</title><link href="ocean.css" rel="stylesheet" type="text/css" title="Ocean" /><script src="haddock-util.js" type="text/javascript"></script><script type="text/javascript">//<![CDATA[
window.onload = function () {pageLoad();setSynopsis("mini_Language-Haskell-Pretty.html");};
//]]>
</script></head><body><div id="package-header"><ul class="links" id="page-menu"><li><a href="src/Language-Haskell-Pretty.html">Source</a></li><li><a href="index.html">Contents</a></li><li><a href="doc-index.html">Index</a></li></ul><p class="caption">haskell-src-1.0.1.4: Support for manipulating Haskell source code</p></div><div id="content"><div id="module-header"><table class="info"><tr><th>Portability</th><td>portable</td></tr><tr><th>Stability</th><td>experimental</td></tr><tr><th>Maintainer</th><td>libraries@haskell.org</td></tr></table><p class="caption">Language.Haskell.Pretty</p></div><div id="table-of-contents"><p class="caption">Contents</p><ul><li><a href="#g:1">Pretty printing
</a></li><li><a href="#g:2">Pretty-printing styles (from <a href="Text-PrettyPrint-HughesPJ.html">Text.PrettyPrint.HughesPJ</a>)
</a></li><li><a href="#g:3">Haskell formatting modes
</a></li></ul></div><div id="description"><p class="caption">Description</p><div class="doc"><p>Pretty printer for Haskell.
</p></div></div><div id="synopsis"><p id="control.syn" class="caption expander" onclick="toggleSection('syn')">Synopsis</p><ul id="section.syn" class="hide" onclick="toggleSection('syn')"><li class="src short"><span class="keyword">class</span> <a href="#t:Pretty">Pretty</a> a </li><li class="src short"><a href="#v:prettyPrintStyleMode">prettyPrintStyleMode</a> :: <a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> a => <a href="Language-Haskell-Pretty.html#t:Style">Style</a> -> <a href="Language-Haskell-Pretty.html#t:PPHsMode">PPHsMode</a> -> a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a></li><li class="src short"><a href="#v:prettyPrintWithMode">prettyPrintWithMode</a> :: <a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> a => <a href="Language-Haskell-Pretty.html#t:PPHsMode">PPHsMode</a> -> a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a></li><li class="src short"><a href="#v:prettyPrint">prettyPrint</a> :: <a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> a => a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a></li><li class="src short"><span class="keyword">data</span> <a href="#t:Style">Style</a> = <a href="#v:Style">Style</a> {<ul class="subs"><li><a href="#v:mode">mode</a> :: <a href="Language-Haskell-Pretty.html#t:Mode">Mode</a></li><li><a href="#v:lineLength">lineLength</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int">Int</a></li><li><a href="#v:ribbonsPerLine">ribbonsPerLine</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Prelude.html#t:Float">Float</a></li></ul>}</li><li class="src short"><a href="#v:style">style</a> :: <a href="Language-Haskell-Pretty.html#t:Style">Style</a></li><li class="src short"><span class="keyword">data</span> <a href="#t:Mode">Mode</a> <ul class="subs"><li>= <a href="#v:PageMode">PageMode</a> </li><li>| <a href="#v:ZigZagMode">ZigZagMode</a> </li><li>| <a href="#v:LeftMode">LeftMode</a> </li><li>| <a href="#v:OneLineMode">OneLineMode</a> </li></ul></li><li class="src short"><span class="keyword">data</span> <a href="#t:PPHsMode">PPHsMode</a> = <a href="#v:PPHsMode">PPHsMode</a> {<ul class="subs"><li><a href="#v:classIndent">classIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></li><li><a href="#v:doIndent">doIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></li><li><a href="#v:caseIndent">caseIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></li><li><a href="#v:letIndent">letIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></li><li><a href="#v:whereIndent">whereIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></li><li><a href="#v:onsideIndent">onsideIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></li><li><a href="#v:spacing">spacing</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Bool.html#t:Bool">Bool</a></li><li><a href="#v:layout">layout</a> :: <a href="Language-Haskell-Pretty.html#t:PPLayout">PPLayout</a></li><li><a href="#v:linePragmas">linePragmas</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Bool.html#t:Bool">Bool</a></li><li><a href="#v:comments">comments</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Bool.html#t:Bool">Bool</a></li></ul>}</li><li class="src short"><span class="keyword">type</span> <a href="#t:Indent">Indent</a> = <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int">Int</a></li><li class="src short"><span class="keyword">data</span> <a href="#t:PPLayout">PPLayout</a> <ul class="subs"><li>= <a href="#v:PPOffsideRule">PPOffsideRule</a> </li><li>| <a href="#v:PPSemiColon">PPSemiColon</a> </li><li>| <a href="#v:PPInLine">PPInLine</a> </li><li>| <a href="#v:PPNoLayout">PPNoLayout</a> </li></ul></li><li class="src short"><a href="#v:defaultMode">defaultMode</a> :: <a href="Language-Haskell-Pretty.html#t:PPHsMode">PPHsMode</a></li></ul></div><div id="interface"><h1 id="g:1">Pretty printing
</h1><div class="top"><p class="src"><span class="keyword">class</span> <a name="t:Pretty" class="def">Pretty</a> a <a href="src/Language-Haskell-Pretty.html#Pretty" class="link">Source</a></p><div class="doc"><p>Things that can be pretty-printed, including all the syntactic objects
in <a href="Language-Haskell-Syntax.html">Language.Haskell.Syntax</a>.
</p></div><div class="subs instances"><p id="control.i:Pretty" class="caption collapser" onclick="toggleSection('i:Pretty')">Instances</p><div id="section.i:Pretty" class="show"><table><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsGuardedAlt">HsGuardedAlt</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsGuardedAlts">HsGuardedAlts</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsAlt">HsAlt</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsFieldUpdate">HsFieldUpdate</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsStmt">HsStmt</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsPatField">HsPatField</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsPat">HsPat</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsExp">HsExp</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsLiteral">HsLiteral</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsType">HsType</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsQualType">HsQualType</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsSafety">HsSafety</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsGuardedRhs">HsGuardedRhs</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsRhs">HsRhs</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsBangType">HsBangType</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsConDecl">HsConDecl</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsMatch">HsMatch</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsDecl">HsDecl</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsAssoc">HsAssoc</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsImportSpec">HsImportSpec</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsImportDecl">HsImportDecl</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsExportSpec">HsExportSpec</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsModule">HsModule</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsCName">HsCName</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsOp">HsOp</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsQOp">HsQOp</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsName">HsName</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:HsQName">HsQName</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> <a href="Language-Haskell-Syntax.html#t:Module">Module</a></td><td class="doc empty"> </td></tr></table></div></div></div><div class="top"><p class="src"><a name="v:prettyPrintStyleMode" class="def">prettyPrintStyleMode</a> :: <a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> a => <a href="Language-Haskell-Pretty.html#t:Style">Style</a> -> <a href="Language-Haskell-Pretty.html#t:PPHsMode">PPHsMode</a> -> a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a><a href="src/Language-Haskell-Pretty.html#prettyPrintStyleMode" class="link">Source</a></p><div class="doc"><p>pretty-print with a given style and mode.
</p></div></div><div class="top"><p class="src"><a name="v:prettyPrintWithMode" class="def">prettyPrintWithMode</a> :: <a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> a => <a href="Language-Haskell-Pretty.html#t:PPHsMode">PPHsMode</a> -> a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a><a href="src/Language-Haskell-Pretty.html#prettyPrintWithMode" class="link">Source</a></p><div class="doc"><p>pretty-print with the default style and a given mode.
</p></div></div><div class="top"><p class="src"><a name="v:prettyPrint" class="def">prettyPrint</a> :: <a href="Language-Haskell-Pretty.html#t:Pretty">Pretty</a> a => a -> <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Char.html#t:String">String</a><a href="src/Language-Haskell-Pretty.html#prettyPrint" class="link">Source</a></p><div class="doc"><p>pretty-print with the default style and <code><a href="Language-Haskell-Pretty.html#v:defaultMode">defaultMode</a></code>.
</p></div></div><h1 id="g:2">Pretty-printing styles (from <a href="Text-PrettyPrint-HughesPJ.html">Text.PrettyPrint.HughesPJ</a>)
</h1><div class="top"><p class="src"><span class="keyword">data</span> <a name="t:Style" class="def">Style</a> </p><div class="doc"><p>A rendering style.
</p></div><div class="subs constructors"><p class="caption">Constructors</p><table><tr><td class="src"><a name="v:Style" class="def">Style</a></td><td class="doc empty"> </td></tr><tr><td colspan="2"><div class="subs fields"><p class="caption">Fields</p><dl><dt class="src"><a name="v:mode" class="def">mode</a> :: <a href="Language-Haskell-Pretty.html#t:Mode">Mode</a></dt><dd class="doc"><p>The rendering mode
</p></dd><dt class="src"><a name="v:lineLength" class="def">lineLength</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int">Int</a></dt><dd class="doc"><p>Length of line, in chars
</p></dd><dt class="src"><a name="v:ribbonsPerLine" class="def">ribbonsPerLine</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Prelude.html#t:Float">Float</a></dt><dd class="doc"><p>Ratio of ribbon length to line length
</p></dd></dl><div class="clear"></div></div></td></tr></table></div></div><div class="top"><p class="src"><a name="v:style" class="def">style</a> :: <a href="Language-Haskell-Pretty.html#t:Style">Style</a></p><div class="doc"><p>The default style (<code>mode=PageMode, lineLength=100, ribbonsPerLine=1.5</code>).
</p></div></div><div class="top"><p class="src"><span class="keyword">data</span> <a name="t:Mode" class="def">Mode</a> </p><div class="doc"><p>Rendering mode.
</p></div><div class="subs constructors"><p class="caption">Constructors</p><table><tr><td class="src"><a name="v:PageMode" class="def">PageMode</a></td><td class="doc"><p>Normal
</p></td></tr><tr><td class="src"><a name="v:ZigZagMode" class="def">ZigZagMode</a></td><td class="doc"><p>With zig-zag cuts
</p></td></tr><tr><td class="src"><a name="v:LeftMode" class="def">LeftMode</a></td><td class="doc"><p>No indentation, infinitely long lines
</p></td></tr><tr><td class="src"><a name="v:OneLineMode" class="def">OneLineMode</a></td><td class="doc"><p>All on one line
</p></td></tr></table></div></div><h1 id="g:3">Haskell formatting modes
</h1><div class="top"><p class="src"><span class="keyword">data</span> <a name="t:PPHsMode" class="def">PPHsMode</a> <a href="src/Language-Haskell-Pretty.html#PPHsMode" class="link">Source</a></p><div class="doc"><p>Pretty-printing parameters.
</p><p><em>Note:</em> the <code><a href="Language-Haskell-Pretty.html#v:onsideIndent">onsideIndent</a></code> must be positive and less than all other indents.
</p></div><div class="subs constructors"><p class="caption">Constructors</p><table><tr><td class="src"><a name="v:PPHsMode" class="def">PPHsMode</a></td><td class="doc empty"> </td></tr><tr><td colspan="2"><div class="subs fields"><p class="caption">Fields</p><dl><dt class="src"><a name="v:classIndent" class="def">classIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></dt><dd class="doc"><p>indentation of a class or instance
</p></dd><dt class="src"><a name="v:doIndent" class="def">doIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></dt><dd class="doc"><p>indentation of a <code>do</code>-expression
</p></dd><dt class="src"><a name="v:caseIndent" class="def">caseIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></dt><dd class="doc"><p>indentation of the body of a
<code>case</code> expression
</p></dd><dt class="src"><a name="v:letIndent" class="def">letIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></dt><dd class="doc"><p>indentation of the declarations in a
<code>let</code> expression
</p></dd><dt class="src"><a name="v:whereIndent" class="def">whereIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></dt><dd class="doc"><p>indentation of the declarations in a
<code>where</code> clause
</p></dd><dt class="src"><a name="v:onsideIndent" class="def">onsideIndent</a> :: <a href="Language-Haskell-Pretty.html#t:Indent">Indent</a></dt><dd class="doc"><p>indentation added for continuation
lines that would otherwise be offside
</p></dd><dt class="src"><a name="v:spacing" class="def">spacing</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Bool.html#t:Bool">Bool</a></dt><dd class="doc"><p>blank lines between statements?
</p></dd><dt class="src"><a name="v:layout" class="def">layout</a> :: <a href="Language-Haskell-Pretty.html#t:PPLayout">PPLayout</a></dt><dd class="doc"><p>Pretty-printing style to use
</p></dd><dt class="src"><a name="v:linePragmas" class="def">linePragmas</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Bool.html#t:Bool">Bool</a></dt><dd class="doc"><p>add GHC-style <code>LINE</code> pragmas to output?
</p></dd><dt class="src"><a name="v:comments" class="def">comments</a> :: <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Bool.html#t:Bool">Bool</a></dt><dd class="doc"><p>not implemented yet
</p></dd></dl><div class="clear"></div></div></td></tr></table></div></div><div class="top"><p class="src"><span class="keyword">type</span> <a name="t:Indent" class="def">Indent</a> = <a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Int.html#t:Int">Int</a><a href="src/Language-Haskell-Pretty.html#Indent" class="link">Source</a></p></div><div class="top"><p class="src"><span class="keyword">data</span> <a name="t:PPLayout" class="def">PPLayout</a> <a href="src/Language-Haskell-Pretty.html#PPLayout" class="link">Source</a></p><div class="doc"><p>Varieties of layout we can use.
</p></div><div class="subs constructors"><p class="caption">Constructors</p><table><tr><td class="src"><a name="v:PPOffsideRule" class="def">PPOffsideRule</a></td><td class="doc"><p>classical layout
</p></td></tr><tr><td class="src"><a name="v:PPSemiColon" class="def">PPSemiColon</a></td><td class="doc"><p>classical layout made explicit
</p></td></tr><tr><td class="src"><a name="v:PPInLine" class="def">PPInLine</a></td><td class="doc"><p>inline decls, with newlines between them
</p></td></tr><tr><td class="src"><a name="v:PPNoLayout" class="def">PPNoLayout</a></td><td class="doc"><p>everything on a single line
</p></td></tr></table></div><div class="subs instances"><p id="control.i:PPLayout" class="caption collapser" onclick="toggleSection('i:PPLayout')">Instances</p><div id="section.i:PPLayout" class="show"><table><tr><td class="src"><a href="/usr/share/doc/ghc/html/libraries/base-4.3.1.0/Data-Eq.html#t:Eq">Eq</a> <a href="Language-Haskell-Pretty.html#t:PPLayout">PPLayout</a></td><td class="doc empty"> </td></tr></table></div></div></div><div class="top"><p class="src"><a name="v:defaultMode" class="def">defaultMode</a> :: <a href="Language-Haskell-Pretty.html#t:PPHsMode">PPHsMode</a><a href="src/Language-Haskell-Pretty.html#defaultMode" class="link">Source</a></p><div class="doc"><p>The default mode: pretty-print using the offside rule and sensible
defaults.
</p></div></div></div></div><div id="footer"><p>Produced by <a href="http://www.haskell.org/haddock/">Haddock</a> version 2.9.2</p></div></body></html>
