Sophie: ghc-doc-0:6.10.4-1mdv2010.0 i586

ghc-doc-6.10.4-1mdv2010.0.i586.rpm

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<!--Rendered using the Haskell Html Library v0.2-->
<HTML
><HEAD
><META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=UTF-8"
><TITLE
>Data.Either</TITLE
><LINK HREF="haddock.css" REL="stylesheet" TYPE="text/css"
><SCRIPT SRC="haddock-util.js" TYPE="text/javascript"
></SCRIPT
><SCRIPT TYPE="text/javascript"
>window.onload = function () {setSynopsis("mini_Data-Either.html")};</SCRIPT
></HEAD
><BODY
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="topbar"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD
><IMG SRC="haskell_icon.gif" WIDTH="16" HEIGHT="16" ALT=" "
></TD
><TD CLASS="title"
>base-4.1.0.0: Basic libraries</TD
><TD CLASS="topbut"
><A HREF="index.html"
>Contents</A
></TD
><TD CLASS="topbut"
><A HREF="doc-index.html"
>Index</A
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="modulebar"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD
><FONT SIZE="6"
>Data.Either</FONT
></TD
><TD ALIGN="right"
><TABLE CLASS="narrow" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="infohead"
>Portability</TD
><TD CLASS="infoval"
>portable</TD
></TR
><TR
><TD CLASS="infohead"
>Stability</TD
><TD CLASS="infoval"
>experimental</TD
></TR
><TR
><TD CLASS="infohead"
>Maintainer</TD
><TD CLASS="infoval"
>libraries@haskell.org</TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section1"
>Description</TD
></TR
><TR
><TD CLASS="doc"
>The Either type, and associated operations.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section1"
>Synopsis</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A HREF="#t%3AEither"
>Either</A
> a b </TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="decl"
>= <A HREF="#v%3ALeft"
>Left</A
> a</TD
></TR
><TR
><TD CLASS="decl"
>| <A HREF="#v%3ARight"
>Right</A
> b</TD
></TR
></TABLE
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3Aeither"
>either</A
> ::  (a -&gt; c) -&gt; (b -&gt; c) -&gt; <A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b -&gt; c</TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3Alefts"
>lefts</A
> ::  [<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b] -&gt; [a]</TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3Arights"
>rights</A
> ::  [<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b] -&gt; [b]</TD
></TR
><TR
><TD CLASS="s8"
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="#v%3ApartitionEithers"
>partitionEithers</A
> ::  [<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b] -&gt; ([a], [b])</TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="section1"
>Documentation</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><SPAN CLASS="keyword"
>data</SPAN
>  <A NAME="t:Either"
><A NAME="t%3AEither"
></A
></A
><B
>Either</B
> a b </TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="0" CELLPADDING="0"
><TR
><TD CLASS="ndoc"
><P
>The <TT
><A HREF="Data-Either.html#t%3AEither"
>Either</A
></TT
> type represents values with two possibilities: a value of
type <TT
><TT
><A HREF="Data-Either.html#t%3AEither"
>Either</A
></TT
> a b</TT
> is either <TT
><TT
><A HREF="Data-Either.html#v%3ALeft"
>Left</A
></TT
> a</TT
> or <TT
><TT
><A HREF="Data-Either.html#v%3ARight"
>Right</A
></TT
> b</TT
>.
</P
><P
>The <TT
><A HREF="Data-Either.html#t%3AEither"
>Either</A
></TT
> type is sometimes used to represent a value which is
either correct or an error; by convention, the <TT
><A HREF="Data-Either.html#v%3ALeft"
>Left</A
></TT
> constructor is
used to hold an error value and the <TT
><A HREF="Data-Either.html#v%3ARight"
>Right</A
></TT
> constructor is used to
hold a correct value (mnemonic: &quot;right&quot; also means &quot;correct&quot;).
</P
></TD
></TR
><TR
><TD CLASS="section4"
>Constructors</TD
></TR
><TR
><TD CLASS="body"
><TABLE CLASS="vanilla" CELLSPACING="1" CELLPADDING="0"
><TR
><TD CLASS="arg"
><A NAME="v:Left"
><A NAME="v%3ALeft"
></A
></A
><B
>Left</B
> a</TD
><TD CLASS="rdoc"
></TD
></TR
><TR
><TD CLASS="arg"
><A NAME="v:Right"
><A NAME="v%3ARight"
></A
></A
><B
>Right</B
> b</TD
><TD CLASS="rdoc"
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="section4"
><IMG SRC="minus.gif" CLASS="coll" ONCLICK="toggle(this,'i:Either')" ALT="show/hide"
> Instances</TD
></TR
><TR
><TD CLASS="body"
><DIV ID="i:Either" STYLE="display:block;"
><TABLE CLASS="vanilla" CELLSPACING="1" CELLPADDING="0"
><TR
><TD CLASS="decl"
><A HREF="Data-Typeable.html#t%3ATypeable2"
>Typeable2</A
> <A HREF="Data-Either.html#t%3AEither"
>Either</A
></TD
></TR
><TR
><TD CLASS="decl"
><A HREF="Control-Monad.html#t%3AFunctor"
>Functor</A
> (<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a)</TD
></TR
><TR
><TD CLASS="decl"
>(<A HREF="Data-Eq.html#t%3AEq"
>Eq</A
> a, <A HREF="Data-Eq.html#t%3AEq"
>Eq</A
> b) =&gt; <A HREF="Data-Eq.html#t%3AEq"
>Eq</A
> (<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b)</TD
></TR
><TR
><TD CLASS="decl"
>(<A HREF="Data-Data.html#t%3AData"
>Data</A
> a, <A HREF="Data-Data.html#t%3AData"
>Data</A
> b) =&gt; <A HREF="Data-Data.html#t%3AData"
>Data</A
> (<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b)</TD
></TR
><TR
><TD CLASS="decl"
>(<A HREF="Data-Ord.html#t%3AOrd"
>Ord</A
> a, <A HREF="Data-Ord.html#t%3AOrd"
>Ord</A
> b) =&gt; <A HREF="Data-Ord.html#t%3AOrd"
>Ord</A
> (<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b)</TD
></TR
><TR
><TD CLASS="decl"
>(<A HREF="Text-Read.html#t%3ARead"
>Read</A
> a, <A HREF="Text-Read.html#t%3ARead"
>Read</A
> b) =&gt; <A HREF="Text-Read.html#t%3ARead"
>Read</A
> (<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b)</TD
></TR
><TR
><TD CLASS="decl"
>(<A HREF="Text-Show.html#t%3AShow"
>Show</A
> a, <A HREF="Text-Show.html#t%3AShow"
>Show</A
> b) =&gt; <A HREF="Text-Show.html#t%3AShow"
>Show</A
> (<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b)</TD
></TR
></TABLE
></DIV
></TD
></TR
></TABLE
></TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:either"
><A NAME="v%3Aeither"
></A
></A
><B
>either</B
> ::  (a -&gt; c) -&gt; (b -&gt; c) -&gt; <A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b -&gt; c</TD
></TR
><TR
><TD CLASS="doc"
>Case analysis for the <TT
><A HREF="Data-Either.html#t%3AEither"
>Either</A
></TT
> type.
 If the value is <TT
><TT
><A HREF="Data-Either.html#v%3ALeft"
>Left</A
></TT
> a</TT
>, apply the first function to <TT
>a</TT
>;
 if it is <TT
><TT
><A HREF="Data-Either.html#v%3ARight"
>Right</A
></TT
> b</TT
>, apply the second function to <TT
>b</TT
>.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:lefts"
><A NAME="v%3Alefts"
></A
></A
><B
>lefts</B
> ::  [<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b] -&gt; [a]</TD
></TR
><TR
><TD CLASS="doc"
>Extracts from a list of <TT
><A HREF="Data-Either.html#t%3AEither"
>Either</A
></TT
> all the <TT
><A HREF="Data-Either.html#v%3ALeft"
>Left</A
></TT
> elements
 All the <TT
><A HREF="Data-Either.html#v%3ALeft"
>Left</A
></TT
> elements are extracted in order.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:rights"
><A NAME="v%3Arights"
></A
></A
><B
>rights</B
> ::  [<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b] -&gt; [b]</TD
></TR
><TR
><TD CLASS="doc"
>Extracts from a list of <TT
><A HREF="Data-Either.html#t%3AEither"
>Either</A
></TT
> all the <TT
><A HREF="Data-Either.html#v%3ARight"
>Right</A
></TT
> elements
 All the <TT
><A HREF="Data-Either.html#v%3ARight"
>Right</A
></TT
> elements are extracted in order.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="decl"
><A NAME="v:partitionEithers"
><A NAME="v%3ApartitionEithers"
></A
></A
><B
>partitionEithers</B
> ::  [<A HREF="Data-Either.html#t%3AEither"
>Either</A
> a b] -&gt; ([a], [b])</TD
></TR
><TR
><TD CLASS="doc"
>Partitions a list of <TT
><A HREF="Data-Either.html#t%3AEither"
>Either</A
></TT
> into two lists
 All the <TT
><A HREF="Data-Either.html#v%3ALeft"
>Left</A
></TT
> elements are extracted, in order, to the first
 component of the output.  Similarly the <TT
><A HREF="Data-Either.html#v%3ARight"
>Right</A
></TT
> elements are extracted
 to the second component of the output.
</TD
></TR
><TR
><TD CLASS="s15"
></TD
></TR
><TR
><TD CLASS="botbar"
>Produced by <A HREF="http://www.haskell.org/haddock/"
>Haddock</A
> version 2.4.2</TD
></TR
></TABLE
></BODY
></HTML
>