Bare <DATA> outside a while doesn't assign to $_, which is why the output doesn't change in the inner loop. It's the while that does the rewriting trick to while (defined($_=<DATA>)) { ...}, as described in perlsyn.

In reply to Re: Hmmm: while(), file handle and $_ gotcha by moritz
in thread Hmmm: while(), file handle and $_ gotcha by roboticus

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