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<H2>Issue SHARP-O-FOOBAR Writeup</H2>
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<PRE><B>Forum:</B> Public Review<P>
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<B>Issue:</B> <A HREF="iss316.htm">SHARP-O-FOOBAR</A><P>
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<B>References:</B> Loosemore's public review comment #5<P>
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#b, #o, #x, #r reader syntax <P>
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(sections 2.4.8.7 to 2.4.8.10, pages 2-30..2-31)<P>
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<B>Category:</B> CLARIFICATION<P>
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<B>Edit history:</B> 21 Dec 1992, Version 1 by Loosemore<P>
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<B>Status:</B> Proposal CONSEQUENCES-UNDEFINED passed (8+2)-1 on <P>
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letter ballot 93-302.<P>
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<P>
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<P>
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<B>Problem description:<P>
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</B><P>
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Is #ofoobar valid syntax? In other words, what happens if the<P>
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object following #b, #o, #x, or #r doesn't have the syntax of<P>
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a rational in the given radix?<P>
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<P>
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<P>
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<B>Proposal (SHARP-O-FOOBAR:CONSEQUENCES-UNDEFINED):<P>
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</B><P>
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Clarify that the consequences are undefined if the token following<P>
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#b, #o, #x, or #r does not have the syntax of a rational in the given<P>
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radix.<P>
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<P>
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<P>
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<B>Rationale:<P>
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</B><P>
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At least some implementations signal an error. Other implementations<P>
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apparently just rebind <A REL=DEFINITION HREF="../Body/v_rd_bas.htm#STread-baseST"><B>*READ-BASE*</B></A> and call <A REL=DEFINITION HREF="../Body/f_rd_rd.htm#read"><B>READ</B></A> recursively.<P>
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<P>
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<P>
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<B>Current practice:<P>
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</B><P>
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Lucid, CMU CL, and AKCL all signal an error. WCL reads #ofoobar<P>
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as the symbol FOOBAR.<P>
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<P>
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<P>
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<B>Cost to implementors:<P>
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</B><P>
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None.<P>
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<P>
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<P>
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<B>Cost to users:<P>
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</B><P>
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None, since the behavior already differs among implementations.<P>
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<P>
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<P>
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<B>Aesthetics:<P>
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</B><P>
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Being explicitly vague is better than being implicitly vague.<P>
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<P>
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<P>
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<B>Editorial impact:<P>
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</B><P>
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Adding one sentence to each of the four referenced sections.<P>
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<P>
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<P>
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<B>Discussion:<P>
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</B><P>
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<P>
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<P>
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<P>
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<P>
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<P>
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<P>
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<P>
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</PRE>
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