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Re: [ID 20000403.009] uninitialised concatenation???

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From:
simon
Date:
April 4, 2000 21:35
Subject:
Re: [ID 20000403.009] uninitialised concatenation???
Message ID:
slrn8elgis.r9.simon@othersideofthe.earth.li
David Glasser (lists.p5p):
>Does this make anybody happy?

A few (minor) changes would make me very happy indeed. In the spirit of not
exposing the internals to the ordinary user, I think we may want to
avoid talking about opcodes. Also, the error message is displayed by
perl, not by the program! :)

--- pod/perldiag.pod~	Wed Apr  5 13:28:50 2000
+++ pod/perldiag.pod	Wed Apr  5 13:33:06 2000
@@ -3360,6 +3360,13 @@
 interpreted as a "" or a 0, but maybe it was a mistake.  To suppress this
 warning assign a defined value to your variables.
 
+To help you figure out what was undefined, perl tells you what operation you
+used an undefined value in.  Note, however, that perl optimizes your program
+and the operation displayed in the warning may not necessarily appear literally
+in your program.  For example, C<"that $foo"> is usually optimized into C<"that
+" . $foo>, and the warning will refer to the C<concatenation (.)> operator,
+even though there is no C<.> in your program.
+
 =item Useless use of "re" pragma
 
 (W) You did C<use re;> without any arguments.   That isn't very useful.

-- 
`And when you've been *plonk*ed by Simon C., you've been *plonked*
by someone who knows when, and why, and how.' - Mike Andrews, asr

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