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>*read-base* | Common Lisp Nova Spec</TITLE
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><TD ALIGN="LEFT" VALIGN="BASELINE" WIDTH="100%" CLASS="name"
><SPAN CLASS="idx" DATA-KIND="idxref" DATA-TERM="*read-base*"
></SPAN
><SPAN CLASS="cmsy"
>*</SPAN
><B
>read-base</B
><SPAN CLASS="cmsy"
>*</SPAN
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><TD ALIGN="RIGHT" VALIGN="BASELINE" WIDTH="0" NOWRAP="NOWRAP" CLASS="ftype"
><I
>Variable</I
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><DT
><B
>Value Type</B
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><P CLASS="j"
>a <A HREF="26_1_Glossary.html#radix"
><EM CLASS="term"
>radix</EM
></A
>.</P
></DD
><DT
><B
>Initial Value</B
></DT
><DD
><P CLASS="j"
><CODE CLASS="f"
>10</CODE
>.</P
></DD
><DT
><B
>Description</B
></DT
><DD
><P CLASS="j"
>Controls the interpretation of tokens by <A HREF="f_read.html" CLASS="funref"
><B
>read</B
></A
> as being <A HREF="26_1_Glossary.html#integer"
><EM CLASS="term"
>integers</EM
></A
> or <A HREF="26_1_Glossary.html#ratio"
><EM CLASS="term"
>ratios</EM
></A
>. </P
><P CLASS="j"
>The <A HREF="26_1_Glossary.html#value"
><EM CLASS="term"
>value</EM
></A
> of <A HREF="v_read-base.html" CLASS="misc"
><B
>*read-base*</B
></A
>, called the <DFN CLASS="newterm"
><SPAN CLASS="cmbxsl"
>current</SPAN
> <SPAN CLASS="cmbxsl"
>input</SPAN
> <SPAN CLASS="cmbxsl"
>base</SPAN
></DFN
><SPAN CLASS="idx" DATA-KIND="idxterm" DATA-TERM="current input base"
></SPAN
>, is the radix in which <A HREF="26_1_Glossary.html#integer"
><EM CLASS="term"
>integers</EM
></A
> and <A HREF="26_1_Glossary.html#ratio"
><EM CLASS="term"
>ratios</EM
></A
> are to be read by the <A HREF="26_1_Glossary.html#Lisp_reader"
><EM CLASS="term"
>Lisp reader</EM
></A
>. The parsing of other numeric <A HREF="26_1_Glossary.html#type"
><EM CLASS="term"
>types</EM
></A
> (<I CLASS="i"
><I
>e.g.</I
></I
>, <A HREF="26_1_Glossary.html#float"
><EM CLASS="term"
>floats</EM
></A
>) is not affected by this option. </P
><P CLASS="j"
>The effect of <A HREF="v_read-base.html" CLASS="varref"
><B
>*read-base*</B
></A
> on the reading of any particular <A HREF="26_1_Glossary.html#rational"
><EM CLASS="term"
>rational</EM
></A
> number can be locally overridden by explicit use of the <CODE CLASS="f"
>#O</CODE
>, <CODE CLASS="f"
>#X</CODE
>, <CODE CLASS="f"
>#B</CODE
>, or <SPAN CLASS="cmtt"
>#</SPAN
><I CLASS="i"
><I
>n</I
></I
><SPAN CLASS="cmtt"
>R</SPAN
> syntax or by a trailing decimal point.</P
></DD
><DT
><B
>Examples</B
></DT
><DD
><PRE CLASS="screen"
> (dotimes (i 6)
(let ((*read-base* (+ 10. i)))
(let ((object (read-from-string "(\\DAD DAD |BEE| BEE 123. 123)")))
(print (list *read-base* object)))))
<SPAN CLASS="cmr"
>&#8883;</SPAN
> (10 (DAD DAD BEE BEE 123 123))
<SPAN CLASS="cmr"
>&#8883;</SPAN
> (11 (DAD DAD BEE BEE 123 146))
<SPAN CLASS="cmr"
>&#8883;</SPAN
> (12 (DAD DAD BEE BEE 123 171))
<SPAN CLASS="cmr"
>&#8883;</SPAN
> (13 (DAD DAD BEE BEE 123 198))
<SPAN CLASS="cmr"
>&#8883;</SPAN
> (14 (DAD 2701 BEE BEE 123 227))
<SPAN CLASS="cmr"
>&#8883;</SPAN
> (15 (DAD 3088 BEE 2699 123 258))
<SPAN CLASS="cmsy"
><SPAN CLASS="arrow"
>&#8594;</SPAN
></SPAN
> NIL</PRE
></DD
><DT
><B
>Notes</B
></DT
><DD
><P CLASS="j"
>Altering the input radix can be useful when reading data files in special formats.</P
></DD
></DL
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