in reply to Re^3: sub that sets $_
in thread sub that sets $_

definitly not.
use FTest; my $test = new FTest (); print foreach $test->foo; print for $test->foo;
Meanwhile in a module
package FTest; sub new { return bless {}, shift; } sub foo { return 1; } 1;
That code prints "11". I you were correct that would be an endless loop.

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Re^5: sub that sets $_
by anonymized user 468275 (Curate) on Jun 28, 2005 at 13:52 UTC
    I have to pass there because I don't understand what this has to do with $_ being a default for/foreach parameter.

    One world, one people

      I have to pass there because I don't understand what this has to do with $_ being a default for/foreach parameter.
      Well, nothing. $_ is the default variable for a for/foreach loop. That's not the point.

      The point here is that the return value of a subroutine or method does not set $_ automatically. You suggested to use a for/foreach loop instead of a while loop, and that will not work because the method "chunk" is a iterator that only returns a single scalar per call. Thus, since for/foreach works on lists, the loops block will only be executed once.

      In the while-loop however the block will be executed for every iteration until "chunk" returns false.

      To make for/foreach work here, the ChunkReader-class would have to return a list of chunks and that, as said, is a waste of memory.