in reply to Re^2: sub that sets $_
in thread sub that sets $_

No - each iteration returns a chunk into $_ in the for or foreach loop.

One world, one people

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Re^4: sub that sets $_
by holli (Abbot) on Jun 28, 2005 at 13:31 UTC
    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.
      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.