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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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<TITLE>CLHS: Section 2.3.1</TITLE>
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<H2>
2.3.1 Numbers as Tokens</H2> <P>
When a <A REL=DEFINITION HREF="26_glo_t.htm#token"><I>token</I></A> is read, it is interpreted as a <A REL=DEFINITION HREF="26_glo_n.htm#number"><I>number</I></A> or <A REL=DEFINITION HREF="26_glo_s.htm#symbol"><I>symbol</I></A>. The <A REL=DEFINITION HREF="26_glo_t.htm#token"><I>token</I></A> is interpreted as a <A REL=DEFINITION HREF="26_glo_n.htm#number"><I>number</I></A> if it satisfies the syntax for numbers specified in the next figure. <P>
<A NAME="syntaxfornumerictokens"> <PRE>
numeric-token ::= integer |
ratio |
float
integer ::= [sign]
decimal-digit+
decimal-point |
[sign]
digit+
ratio ::= [sign]
{digit}+
slash
{digit}+
float ::= [sign]
{decimal-digit}*
decimal-point
{decimal-digit}+
[exponent]
|
[sign]
{decimal-digit}+
[decimal-point
{decimal-digit}*]
exponent
exponent ::= exponent-marker
[sign]
{digit}+
sign---a <A REL=DEFINITION HREF="26_glo_s.htm#sign">sign</A>.
slash---a <A REL=DEFINITION HREF="26_glo_s.htm#slash">slash</A>
decimal-point---a <A REL=DEFINITION HREF="26_glo_d.htm#dot">dot</A>.
exponent-marker---an <A REL=DEFINITION HREF="26_glo_e.htm#exponent_marker">exponent marker</A>.
decimal-digit---a <A REL=DEFINITION HREF="26_glo_d.htm#digit">digit</A> in <A REL=DEFINITION HREF="26_glo_r.htm#radix">radix</A> 10.
digit---a <A REL=DEFINITION HREF="26_glo_d.htm#digit">digit</A> in the current input radix.
</PRE>
<P><B>Figure 2-9. Syntax for Numeric Tokens</B></A> <P>
<A REL=CHILD HREF="02_caa.htm"><H2>
2.3.1.1 Potential Numbers as Tokens</H2></A><P><HR>
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