63 lines
3.5 KiB
HTML
63 lines
3.5 KiB
HTML
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<!-- Common Lisp HyperSpec (TM), version 7.0 generated by Kent M. Pitman on Mon, 11-Apr-2005 2:31am EDT -->
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<HTML>
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<HEAD>
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<TITLE>CLHS: Function IDENTITY</TITLE>
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<BODY>
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<H1><A REV=MADE HREF="http://www.lispworks.com/"><IMG WIDTH=80 HEIGHT=65 ALT="[LISPWORKS]" SRC="../Graphics/LWSmall.gif" ALIGN=Bottom></A><A REL=TOP HREF="../Front/index.htm"><IMG WIDTH=237 HEIGHT=65 ALT="[Common Lisp HyperSpec (TM)]" SRC="../Graphics/CLHS_Sm.gif" ALIGN=Bottom></A> <A REL=PREV HREF="f_equalp.htm"><IMG WIDTH=40 HEIGHT=40 ALT="[Previous]" SRC="../Graphics/Prev.gif" ALIGN=Bottom></A><A REL=UP HREF="c_data_a.htm"><IMG WIDTH=40 HEIGHT=40 ALT="[Up]" SRC="../Graphics/Up.gif" ALIGN=Bottom></A><A REL=NEXT HREF="f_comple.htm"><IMG WIDTH=40 HEIGHT=40 ALT="[Next]" SRC="../Graphics/Next.gif" ALIGN=Bottom></A></H1>
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<HR>
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<A NAME="identity"><I>Function</I> <B>IDENTITY</B></A> <P>
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<P><B>Syntax:</B><P>
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<P>
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<B>identity</B> <I>object</I> => <I>object</I><P>
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<P>
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<P><B>Arguments and Values:</B><P>
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<P>
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<I>object</I>---an <A REL=DEFINITION HREF="26_glo_o.htm#object"><I>object</I></A>. <P>
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<P><B>Description:</B><P>
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<P>
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Returns its argument <I>object</I>. <P>
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<P><B>Examples:</B><P>
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<P>
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<PRE>
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(identity 101) => 101
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(mapcan #'identity (list (list 1 2 3) '(4 5 6))) => (1 2 3 4 5 6)
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</PRE>
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</TT> <P>
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<P><B>Side Effects:</B> None.
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<P>
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<P><B>Affected By:</B> None.
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<P>
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<P><B>Exceptional Situations:</B> None.
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<P>
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<P><B>See Also:</B> None.
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<P>
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<P><B>Notes:</B><P>
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<P>
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<A REL=DEFINITION HREF="#identity"><B>identity</B></A> is intended for use with functions that require a <A REL=DEFINITION HREF="26_glo_f.htm#function"><I>function</I></A> as an argument. <P>
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<TT>(eql x (identity x))</TT> returns <A REL=DEFINITION HREF="26_glo_t.htm#true"><I>true</I></A> for all possible values of <I>x</I>, but <TT>(eq x (identity x))</TT> might return <A REL=DEFINITION HREF="26_glo_f.htm#false"><I>false</I></A> when <I>x</I> is a <A REL=DEFINITION HREF="26_glo_n.htm#number"><I>number</I></A> or <A REL=DEFINITION HREF="26_glo_c.htm#character"><I>character</I></A>. <P>
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<A REL=DEFINITION HREF="#identity"><B>identity</B></A> could be defined by <P>
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<PRE>
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(defun identity (x) x)
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</PRE>
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</TT> <P>
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<HR>
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<A REL=NAVIGATOR HREF="../Front/StartPts.htm"><IMG WIDTH=80 HEIGHT=40 ALT="[Starting Points]" SRC="../Graphics/StartPts.gif" ALIGN=Bottom></A><A REL=TOC HREF="../Front/Contents.htm"><IMG WIDTH=80 HEIGHT=40 ALT="[Contents]" SRC="../Graphics/Contents.gif" ALIGN=Bottom></A><A REL=INDEX HREF="../Front/X_Master.htm"><IMG WIDTH=80 HEIGHT=40 ALT="[Index]" SRC="../Graphics/Index.gif" ALIGN=Bottom></A><A REL=INDEX HREF="../Front/X_Symbol.htm"><IMG WIDTH=80 HEIGHT=40 ALT="[Symbols]" SRC="../Graphics/Symbols.gif" ALIGN=Bottom></A><A REL=GLOSSARY HREF="../Body/26_a.htm"><IMG WIDTH=80 HEIGHT=40 ALT="[Glossary]" SRC="../Graphics/Glossary.gif" ALIGN=Bottom></A><A HREF="../Front/X3J13Iss.htm"><IMG WIDTH=80 HEIGHT=40 ALT="[Issues]" SRC="../Graphics/Issues.gif" ALIGN=Bottom></A><BR>
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<A REL=COPYRIGHT HREF="../Front/Help.htm#Legal"><I>Copyright 1996-2005, LispWorks Ltd. All rights reserved.</I></A><P>
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