The code below gives error Global symbol "$x" requires explicit package name. 

use strict; 
use warnings;
sub f { $_[0]==15 }  
if((my $x=15) && f($x)) { print "OK\n" }'

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Now I admit that this is a somewhat unconventional construct, but taking the perl docs at face value, I thought this should work. For instance, my says
A "my" declares the listed variables to be local (lexically) to the enclosing block, file, or "eval".
which means that $x should be interpreted as lexical, not global, in the call of f. Further, && guarantees left-to-right evaluation, so $x should be defined when f is called, so I had expected the output of the program being OK. Of course I can easily rewrite it by declaring $x one line earlier, but I wonder why it does not work the way I tried it.

-- 
Ronald Fischer <ynnor@mm.st>

In reply to Declaring a lexical within a 'if' condition by rovf

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