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Postings from February 2002
On Thu, 7 Feb 2002, Brian Hayes wrote:
> It appears the problem was using the foreach statement instead of while.
> I have not tested this extensively, but using foreach the whole text
> file (or output of pipe) is read into memory before continuing, but
> using while (and probably for) each line is processed as it is read.
Yes indeed it does, because foreach operates on a list, where as while
operates on a boolean value returned from an expression (which means
scalar context). So if you do
foreach(<FILE>) { }
It will put <FILE> into the list context and slurp the entire thing up
into a list. 'for' will do the same thing. It also operates on a list
(foreach and for are aliases for each other).
-- Brett
http://www.chapelperilous.net/
------------------------------------------------------------------------
As you grow older, you will still do foolish things, but you will do them
with much more enthusiasm.
-- The Cowboy
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