52 lines
4 KiB
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52 lines
4 KiB
HTML
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<TITLE>CLHS: Constant Variable T</TITLE>
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<A NAME="t"><I>Constant Variable</I> <B>T</B></A> <P>
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<P><B>Constant Value:</B><P>
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<P>
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<A REL=DEFINITION HREF="a_t.htm#t"><B>t</B></A>. <P>
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<P><B>Description:</B><P>
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<P>
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The <A REL=DEFINITION HREF="26_glo_b.htm#boolean"><I>boolean</I></A> representing true, and the canonical <A REL=DEFINITION HREF="26_glo_g.htm#generalized_boolean"><I>generalized boolean</I></A> representing true. Although any <A REL=DEFINITION HREF="26_glo_o.htm#object"><I>object</I></A> other than <A REL=DEFINITION HREF="a_nil.htm#nil"><B>nil</B></A> is considered <A REL=DEFINITION HREF="26_glo_t.htm#true"><I>true</I></A>, <A REL=DEFINITION HREF="a_t.htm#t"><B>t</B></A> is generally used when there is no special reason to prefer one such <A REL=DEFINITION HREF="26_glo_o.htm#object"><I>object</I></A> over another. <P>
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The <A REL=DEFINITION HREF="26_glo_s.htm#symbol"><I>symbol</I></A> <A REL=DEFINITION HREF="a_t.htm#t"><B>t</B></A> is also sometimes used for other purposes as well. For example, as the <A REL=DEFINITION HREF="26_glo_n.htm#name"><I>name</I></A> of a <A REL=DEFINITION HREF="26_glo_c.htm#class"><I>class</I></A>, as a <A REL=DEFINITION HREF="26_glo_d.htm#designator"><I>designator</I></A> (e.g., a <A REL=DEFINITION HREF="26_glo_s.htm#stream_designator"><I>stream designator</I></A>) or as a special symbol for some syntactic reason (e.g., in <A REL=DEFINITION HREF="m_case_.htm#case"><B>case</B></A> and <A REL=DEFINITION HREF="m_tpcase.htm#typecase"><B>typecase</B></A> to label the <I>otherwise-clause</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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t => T
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(eq t 't) => <A REL=DEFINITION HREF="26_glo_t.htm#true">true</A>
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(find-class 't) => #<CLASS T 610703333>
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(case 'a (a 1) (t 2)) => 1
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(case 'b (a 1) (t 2)) => 2
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(prin1 'hello t)
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>> HELLO
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=> HELLO
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</PRE>
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</TT> <P>
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<P><B>See Also:</B><P>
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<P>
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<A REL=DEFINITION HREF="v_nil.htm#nil"><B>nil</B></A> <P>
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<P><B>Notes:</B> None.
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