68 lines
4.8 KiB
HTML
68 lines
4.8 KiB
HTML
<!-- Common Lisp HyperSpec (TM), version 7.0 generated by Kent M. Pitman on Mon, 11-Apr-2005 2:31am EDT -->
|
|
<HTML>
|
|
<HEAD>
|
|
<TITLE>CLHS: Macro OR</TITLE>
|
|
<LINK HREF="../Data/clhs.css" REL="stylesheet" TYPE="text/css" />
|
|
<META HTTP-EQUIV="Author" CONTENT="Kent M. Pitman">
|
|
<META HTTP-EQUIV="Organization" CONTENT="LispWorks Ltd.">
|
|
<LINK REL=TOP HREF="../Front/index.htm">
|
|
<LINK REL=COPYRIGHT HREF="../Front/Help.htm#Legal">
|
|
<LINK REL=DISCLAIMER HREF="../Front/Help.htm#Disclaimer">
|
|
<LINK REL=PREV HREF="s_if.htm">
|
|
<LINK REL=UP HREF="c_data_a.htm">
|
|
<LINK REL=NEXT HREF="m_when_.htm">
|
|
</HEAD>
|
|
<BODY>
|
|
<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="s_if.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="m_when_.htm"><IMG WIDTH=40 HEIGHT=40 ALT="[Next]" SRC="../Graphics/Next.gif" ALIGN=Bottom></A></H1>
|
|
|
|
<HR>
|
|
|
|
<A NAME="or"><I>Macro</I> <B>OR</B></A> <P>
|
|
<P><B>Syntax:</B><P>
|
|
<P>
|
|
|
|
<B>or</B> <I><I>form</I><B>*</B></I> => <I><I>results</I><B>*</B></I><P>
|
|
<P>
|
|
<P><B>Arguments and Values:</B><P>
|
|
<P>
|
|
<I>form</I>---a <A REL=DEFINITION HREF="26_glo_f.htm#form"><I>form</I></A>. <P>
|
|
<I>results</I>---the <A REL=DEFINITION HREF="26_glo_v.htm#value"><I>values</I></A> or <A REL=DEFINITION HREF="26_glo_p.htm#primary_value"><I>primary value</I></A> (see below) resulting from the evaluation of the last <I>form</I> executed or <A REL=DEFINITION HREF="a_nil.htm#nil"><B>nil</B></A>. <P>
|
|
<P><B>Description:</B><P>
|
|
<P>
|
|
<A REL=DEFINITION HREF="#or"><B>or</B></A> evaluates each <I>form</I>, one at a time, from left to right. The evaluation of all <I>forms</I> terminates when a <I>form</I> evaluates to <A REL=DEFINITION HREF="26_glo_t.htm#true"><I>true</I></A> (i.e., something other than <A REL=DEFINITION HREF="a_nil.htm#nil"><B>nil</B></A>). <P>
|
|
If the <A REL=DEFINITION HREF="26_glo_e.htm#evaluation"><I>evaluation</I></A> of any <I>form</I> other than the last returns a <A REL=DEFINITION HREF="26_glo_p.htm#primary_value"><I>primary value</I></A> that is <A REL=DEFINITION HREF="26_glo_t.htm#true"><I>true</I></A>, <A REL=DEFINITION HREF="#or"><B>or</B></A> immediately returns that <A REL=DEFINITION HREF="26_glo_v.htm#value"><I>value</I></A> (but no additional <A REL=DEFINITION HREF="26_glo_v.htm#value"><I>values</I></A>) without evaluating the remaining <I>forms</I>. If every <I>form</I> but the last returns <A REL=DEFINITION HREF="26_glo_f.htm#false"><I>false</I></A> as its <A REL=DEFINITION HREF="26_glo_p.htm#primary_value"><I>primary value</I></A>, <A REL=DEFINITION HREF="#or"><B>or</B></A> returns all <A REL=DEFINITION HREF="26_glo_v.htm#value"><I>values</I></A> returned by the last <I>form</I>. If no <I>forms</I> are supplied, <A REL=DEFINITION HREF="#or"><B>or</B></A> returns <A REL=DEFINITION HREF="a_nil.htm#nil"><B>nil</B></A>. <P>
|
|
<P><B>Examples:</B><P>
|
|
<P>
|
|
<PRE>
|
|
(or) => NIL
|
|
(setq temp0 nil temp1 10 temp2 20 temp3 30) => 30
|
|
(or temp0 temp1 (setq temp2 37)) => 10
|
|
temp2 => 20
|
|
(or (incf temp1) (incf temp2) (incf temp3)) => 11
|
|
temp1 => 11
|
|
temp2 => 20
|
|
temp3 => 30
|
|
(or (values) temp1) => 11
|
|
(or (values temp1 temp2) temp3) => 11
|
|
(or temp0 (values temp1 temp2)) => 11, 20
|
|
(or (values temp0 temp1) (values temp2 temp3)) => 20, 30
|
|
</PRE>
|
|
</TT> <P>
|
|
<P><B>Side Effects:</B> None.
|
|
<P>
|
|
<P><B>Affected By:</B> None.
|
|
<P>
|
|
<P><B>Exceptional Situations:</B> None.
|
|
<P>
|
|
<P><B>See Also:</B><P>
|
|
<P>
|
|
<A REL=DEFINITION HREF="m_and.htm#and"><B>and</B></A>, <A REL=DEFINITION HREF="f_everyc.htm#some"><B>some</B></A>, <A REL=DEFINITION HREF="m_when_.htm#unless"><B>unless</B></A> <P>
|
|
<P><B>Notes:</B> None.
|
|
<P>
|
|
<HR>
|
|
|
|
<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>
|
|
|
|
<A REL=COPYRIGHT HREF="../Front/Help.htm#Legal"><I>Copyright 1996-2005, LispWorks Ltd. All rights reserved.</I></A><P>
|
|
</BODY>
|
|
</HTML>
|