<!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>Data.Array.MArray</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_Data-Array-MArray.html");}; //]]> </script></head><body><div id="package-header"><ul class="links" id="page-menu"><li><a href="index.html">Contents</a></li><li><a href="doc-index.html">Index</a></li></ul><p class="caption">array-0.4.0.0: Mutable and immutable arrays</p></div><div id="content"><div id="module-header"><table class="info"><tr><th>Portability</th><td>non-portable (uses Data.Array.Base)</td></tr><tr><th>Stability</th><td>experimental</td></tr><tr><th>Maintainer</th><td>libraries@haskell.org</td></tr><tr><th>Safe Haskell</th><td>None</td></tr></table><p class="caption">Data.Array.MArray</p></div><div id="table-of-contents"><p class="caption">Contents</p><ul><li><a href="#g:1">Class of mutable array types </a></li><li><a href="#g:2">The <code>Ix</code> class and operations </a></li><li><a href="#g:3">Constructing mutable arrays </a></li><li><a href="#g:4">Reading and writing mutable arrays </a></li><li><a href="#g:5">Derived arrays </a></li><li><a href="#g:6">Deconstructing mutable arrays </a></li><li><a href="#g:7">Conversions between mutable and immutable arrays </a></li></ul></div><div id="description"><p class="caption">Description</p><div class="doc"><p>An overloaded interface to mutable arrays. For array types which can be used with this interface, see <a href="Data-Array-IO.html">Data.Array.IO</a>, <a href="Data-Array-ST.html">Data.Array.ST</a>, and <a href="Data-Array-Storable.html">Data.Array.Storable</a>. </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="../base-4.5.1.0/Control-Monad.html#t:Monad">Monad</a> m => <a href="#t:MArray">MArray</a> a e m <span class="keyword">where</span><ul class="subs"><li><a href="#v:getBounds">getBounds</a> :: <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i => a i e -> m (i, i)</li><li><a href="#v:newArray">newArray</a> :: <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i => (i, i) -> e -> m (a i e)</li><li><a href="#v:newArray_">newArray_</a> :: <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i => (i, i) -> m (a i e)</li></ul></li><li class="src short">module <a href="../base-4.5.1.0/Data-Ix.html">Data.Ix</a></li><li class="src short"><a href="#v:newListArray">newListArray</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => (i, i) -> [e] -> m (a i e)</li><li class="src short"><a href="#v:readArray">readArray</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => a i e -> i -> m e</li><li class="src short"><a href="#v:writeArray">writeArray</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => a i e -> i -> e -> m ()</li><li class="src short"><a href="#v:mapArray">mapArray</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e' m, <a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => (e' -> e) -> a i e' -> m (a i e)</li><li class="src short"><a href="#v:mapIndices">mapIndices</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> j) => (i, i) -> (i -> j) -> a j e -> m (a i e)</li><li class="src short"><a href="#v:getElems">getElems</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => a i e -> m [e]</li><li class="src short"><a href="#v:getAssocs">getAssocs</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => a i e -> m [(i, e)]</li><li class="src short"><a href="#v:freeze">freeze</a> :: (<a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="Data-Array-IArray.html#t:IArray">IArray</a> b e) => a i e -> m (b i e)</li><li class="src short"><a href="#v:unsafeFreeze">unsafeFreeze</a> :: (<a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="Data-Array-IArray.html#t:IArray">IArray</a> b e) => a i e -> m (b i e)</li><li class="src short"><a href="#v:thaw">thaw</a> :: (<a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="Data-Array-IArray.html#t:IArray">IArray</a> a e, <a href="Data-Array-MArray.html#t:MArray">MArray</a> b e m) => a i e -> m (b i e)</li><li class="src short"><a href="#v:unsafeThaw">unsafeThaw</a> :: (<a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="Data-Array-IArray.html#t:IArray">IArray</a> a e, <a href="Data-Array-MArray.html#t:MArray">MArray</a> b e m) => a i e -> m (b i e)</li></ul></div><div id="interface"><h1 id="g:1">Class of mutable array types </h1><div class="top"><p class="src"><span class="keyword">class</span> <a href="../base-4.5.1.0/Control-Monad.html#t:Monad">Monad</a> m => <a name="t:MArray" class="def">MArray</a> a e m <span class="keyword">where</span></p><div class="doc"><p>Class of mutable array types. </p><p>An array type has the form <code>(a i e)</code> where <code>a</code> is the array type constructor (kind <code>* -> * -> *</code>), <code>i</code> is the index type (a member of the class <code><a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a></code>), and <code>e</code> is the element type. </p><p>The <code>MArray</code> class is parameterised over both <code>a</code> and <code>e</code> (so that instances specialised to certain element types can be defined, in the same way as for <code><a href="Data-Array-IArray.html#t:IArray">IArray</a></code>), and also over the type of the monad, <code>m</code>, in which the mutable array will be manipulated. </p></div><div class="subs methods"><p class="caption">Methods</p><p class="src"><a name="v:getBounds" class="def">getBounds</a> :: <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i => a i e -> m (i, i)</p><div class="doc"><p>Returns the bounds of the array </p></div><p class="src"><a name="v:newArray" class="def">newArray</a> :: <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i => (i, i) -> e -> m (a i e)</p><div class="doc"><p>Builds a new array, with every element initialised to the supplied value. </p></div><p class="src"><a name="v:newArray_" class="def">newArray_</a> :: <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i => (i, i) -> m (a i e)</p><div class="doc"><p>Builds a new array, with every element initialised to an undefined value. In a monadic context in which operations must be deterministic (e.g. the ST monad), the array elements are initialised to a fixed but undefined value, such as zero. </p></div></div><div class="subs instances"><p id="control.i:MArray" class="caption collapser" onclick="toggleSection('i:MArray')">Instances</p><div id="section.i:MArray" class="show"><table><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOArray">IOArray</a> e <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Bool.html#t:Bool">Bool</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Char.html#t:Char">Char</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Prelude.html#t:Double">Double</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Prelude.html#t:Float">Float</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Int.html#t:Int">Int</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Int.html#t:Int8">Int8</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Int.html#t:Int16">Int16</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Int.html#t:Int32">Int32</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Int.html#t:Int64">Int64</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Word.html#t:Word">Word</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Word.html#t:Word8">Word8</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Word.html#t:Word16">Word16</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Word.html#t:Word32">Word32</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> <a href="../base-4.5.1.0/Data-Word.html#t:Word64">Word64</a> <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="../base-4.5.1.0/Foreign-Storable.html#t:Storable">Storable</a> e => <a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-Storable.html#t:StorableArray">StorableArray</a> e <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> (<a href="../base-4.5.1.0/Foreign-StablePtr.html#t:StablePtr">StablePtr</a> a) <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> (<a href="../base-4.5.1.0/Foreign-Ptr.html#t:Ptr">Ptr</a> a) <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> <a href="Data-Array-IO.html#t:IOUArray">IOUArray</a> (<a href="../base-4.5.1.0/Foreign-Ptr.html#t:FunPtr">FunPtr</a> a) <a href="../base-4.5.1.0/System-IO.html#t:IO">IO</a></td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STArray">STArray</a> s) e (<a href="../base-4.5.1.0/Control-Monad-ST-Lazy-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STArray">STArray</a> s) e (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Word.html#t:Word64">Word64</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Word.html#t:Word32">Word32</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Word.html#t:Word16">Word16</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Word.html#t:Word8">Word8</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Int.html#t:Int64">Int64</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Int.html#t:Int32">Int32</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Int.html#t:Int16">Int16</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Int.html#t:Int8">Int8</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Prelude.html#t:Double">Double</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Prelude.html#t:Float">Float</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Word.html#t:Word">Word</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Int.html#t:Int">Int</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Char.html#t:Char">Char</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) <a href="../base-4.5.1.0/Data-Bool.html#t:Bool">Bool</a> (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) (<a href="../base-4.5.1.0/Foreign-StablePtr.html#t:StablePtr">StablePtr</a> a) (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) (<a href="../base-4.5.1.0/Foreign-Ptr.html#t:FunPtr">FunPtr</a> a) (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr><tr><td class="src"><a href="Data-Array-MArray.html#t:MArray">MArray</a> (<a href="Data-Array-ST.html#t:STUArray">STUArray</a> s) (<a href="../base-4.5.1.0/Foreign-Ptr.html#t:Ptr">Ptr</a> a) (<a href="../base-4.5.1.0/Control-Monad-ST-Safe.html#t:ST">ST</a> s)</td><td class="doc empty"> </td></tr></table></div></div></div><h1 id="g:2">The <code>Ix</code> class and operations </h1><div class="top"><p class="src">module <a href="../base-4.5.1.0/Data-Ix.html">Data.Ix</a></p></div><h1 id="g:3">Constructing mutable arrays </h1><div class="top"><p class="src"><a name="v:newListArray" class="def">newListArray</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => (i, i) -> [e] -> m (a i e)</p><div class="doc"><p>Constructs a mutable array from a list of initial elements. The list gives the elements of the array in ascending order beginning with the lowest index. </p></div></div><h1 id="g:4">Reading and writing mutable arrays </h1><div class="top"><p class="src"><a name="v:readArray" class="def">readArray</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => a i e -> i -> m e</p><div class="doc"><p>Read an element from a mutable array </p></div></div><div class="top"><p class="src"><a name="v:writeArray" class="def">writeArray</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => a i e -> i -> e -> m ()</p><div class="doc"><p>Write an element in a mutable array </p></div></div><h1 id="g:5">Derived arrays </h1><div class="top"><p class="src"><a name="v:mapArray" class="def">mapArray</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e' m, <a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => (e' -> e) -> a i e' -> m (a i e)</p><div class="doc"><p>Constructs a new array derived from the original array by applying a function to each of the elements. </p></div></div><div class="top"><p class="src"><a name="v:mapIndices" class="def">mapIndices</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> j) => (i, i) -> (i -> j) -> a j e -> m (a i e)</p><div class="doc"><p>Constructs a new array derived from the original array by applying a function to each of the indices. </p></div></div><h1 id="g:6">Deconstructing mutable arrays </h1><div class="top"><p class="src"><a name="v:getElems" class="def">getElems</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => a i e -> m [e]</p><div class="doc"><p>Return a list of all the elements of a mutable array </p></div></div><div class="top"><p class="src"><a name="v:getAssocs" class="def">getAssocs</a> :: (<a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i) => a i e -> m [(i, e)]</p><div class="doc"><p>Return a list of all the associations of a mutable array, in index order. </p></div></div><h1 id="g:7">Conversions between mutable and immutable arrays </h1><div class="top"><p class="src"><a name="v:freeze" class="def">freeze</a> :: (<a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="Data-Array-IArray.html#t:IArray">IArray</a> b e) => a i e -> m (b i e)</p><div class="doc"><p>Converts a mutable array (any instance of <code><a href="Data-Array-MArray.html#t:MArray">MArray</a></code>) to an immutable array (any instance of <code><a href="Data-Array-IArray.html#t:IArray">IArray</a></code>) by taking a complete copy of it. </p></div></div><div class="top"><p class="src"><a name="v:unsafeFreeze" class="def">unsafeFreeze</a> :: (<a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="Data-Array-MArray.html#t:MArray">MArray</a> a e m, <a href="Data-Array-IArray.html#t:IArray">IArray</a> b e) => a i e -> m (b i e)</p><div class="doc"><div class="warning"><p>Deprecated: Please import from Data.Array.Unsafe instead; This will be removed in the next release</p></div><p>Converts an mutable array into an immutable array. The implementation may either simply cast the array from one type to the other without copying the array, or it may take a full copy of the array. </p><p>Note that because the array is possibly not copied, any subsequent modifications made to the mutable version of the array may be shared with the immutable version. It is safe to use, therefore, if the mutable version is never modified after the freeze operation. </p><p>The non-copying implementation is supported between certain pairs of array types only; one constraint is that the array types must have identical representations. In GHC, The following pairs of array types have a non-copying O(1) implementation of <code><a href="Data-Array-MArray.html#v:unsafeFreeze">unsafeFreeze</a></code>. Because the optimised versions are enabled by specialisations, you will need to compile with optimisation (-O) to get them. </p><ul><li> <code><a href="Data-Array-IO.html#t:IOUArray">IOUArray</a></code> -> <code><a href="Data-Array-Unboxed.html#t:UArray">UArray</a></code> </li><li> <code><a href="Data-Array-ST.html#t:STUArray">STUArray</a></code> -> <code><a href="Data-Array-Unboxed.html#t:UArray">UArray</a></code> </li><li> <code><a href="Data-Array-IO.html#t:IOArray">IOArray</a></code> -> <code><a href="Data-Array.html#t:Array">Array</a></code> </li><li> <code><a href="Data-Array-ST.html#t:STArray">STArray</a></code> -> <code><a href="Data-Array.html#t:Array">Array</a></code> </li></ul></div></div><div class="top"><p class="src"><a name="v:thaw" class="def">thaw</a> :: (<a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="Data-Array-IArray.html#t:IArray">IArray</a> a e, <a href="Data-Array-MArray.html#t:MArray">MArray</a> b e m) => a i e -> m (b i e)</p><div class="doc"><p>Converts an immutable array (any instance of <code><a href="Data-Array-IArray.html#t:IArray">IArray</a></code>) into a mutable array (any instance of <code><a href="Data-Array-MArray.html#t:MArray">MArray</a></code>) by taking a complete copy of it. </p></div></div><div class="top"><p class="src"><a name="v:unsafeThaw" class="def">unsafeThaw</a> :: (<a href="../base-4.5.1.0/Data-Ix.html#t:Ix">Ix</a> i, <a href="Data-Array-IArray.html#t:IArray">IArray</a> a e, <a href="Data-Array-MArray.html#t:MArray">MArray</a> b e m) => a i e -> m (b i e)</p><div class="doc"><div class="warning"><p>Deprecated: Please import from Data.Array.Unsafe instead; This will be removed in the next release</p></div><p>Converts an immutable array into a mutable array. The implementation may either simply cast the array from one type to the other without copying the array, or it may take a full copy of the array. </p><p>Note that because the array is possibly not copied, any subsequent modifications made to the mutable version of the array may be shared with the immutable version. It is only safe to use, therefore, if the immutable array is never referenced again in this thread, and there is no possibility that it can be also referenced in another thread. If you use an unsafeThaw<em>write</em>unsafeFreeze sequence in a multi-threaded setting, then you must ensure that this sequence is atomic with respect to other threads, or a garbage collector crash may result (because the write may be writing to a frozen array). </p><p>The non-copying implementation is supported between certain pairs of array types only; one constraint is that the array types must have identical representations. In GHC, The following pairs of array types have a non-copying O(1) implementation of <code><a href="Data-Array-MArray.html#v:unsafeThaw">unsafeThaw</a></code>. Because the optimised versions are enabled by specialisations, you will need to compile with optimisation (-O) to get them. </p><ul><li> <code><a href="Data-Array-Unboxed.html#t:UArray">UArray</a></code> -> <code><a href="Data-Array-IO.html#t:IOUArray">IOUArray</a></code> </li><li> <code><a href="Data-Array-Unboxed.html#t:UArray">UArray</a></code> -> <code><a href="Data-Array-ST.html#t:STUArray">STUArray</a></code> </li><li> <code><a href="Data-Array.html#t:Array">Array</a></code> -> <code><a href="Data-Array-IO.html#t:IOArray">IOArray</a></code> </li><li> <code><a href="Data-Array.html#t:Array">Array</a></code> -> <code><a href="Data-Array-ST.html#t:STArray">STArray</a></code> </li></ul></div></div></div></div><div id="footer"><p>Produced by <a href="http://www.haskell.org/haddock/">Haddock</a> version 2.11.0</p></div></body></html>