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Postings from October 2013
Konrad Borowski wrote:
>I checked. For some reason, subroutine or `do` block ending with `while` block
>or `for` block always returns empty string
The standard false value is an empty string. The last thing evaluated
by a while statement is the condition that comes up false to cause
termination of the loop. The return value is normally the actual
false value used:
$ perl -lwe 'print do { while($_) {} } // "undef" for 0, undef'
0
undef
but it wasn't always thus when constant folding got involved:
$ perl5.16.3 -lwe 'print do { while(0) {} } // "undef"'
undef
$ perl5.18.1 -lwe 'print do { while(0) {} } // "undef"'
0
-zefram
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