The actions will be much the same, but the way it works is rather different: foreach takes a list, which means that before the loop starts the whole of the input file is read, building a list of lines on perl's internal stack and then iterating over that list.

while, on the other hand, reads one line at a time and performs the block on that line before reading the next line. This can use far less memory, and so is usually preferable.

Hugo

In reply to Re: foreach question by hv
in thread foreach question by glwtta

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