I don't see any difference between "modifying" and "setting" $_. If the sub called a a built-in that returns a result in $_ (like magic while(<>)), it will clobber the value in the caller's foreach.

If the sub aliased it, using local or something like foreach which I assumes rebinds without changing the value, that would indeed be different.

I'm supposing that the reason I don't see this as a problem in real scripts is that I don't use the implicit loop with nontrivial bodies—I name the iteration variable. I suppose people who heavily use map might get bit with it more.

—John

In reply to Reii: Should we Localize $_ ? by John M. Dlugosz
in thread Should we Localize $_ ? by John M. Dlugosz

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