Re: Re: Trying to read a filehandle inside a loop

Thanks for your explanation. I can see now that the foreach has 'slurped' the data from the filehandle, so there is no data to read inside the loop. Why doesn't the 'while' loop slurp the data too? I'll have a look in perlsyn I think! Cheers.

Comment on Re: Re: Trying to read a filehandle inside a loop

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Re: Re: Re: Trying to read a filehandle inside a loop by broquaint (Abbot) on Oct 23, 2002 at 09:42 UTC
Why doesn't the 'while' loop slurp the data too? Because the filehandle is only evaulated in a scalar context, so you'll only get one line per iteration. Whereas a `foreach` loop evaluates the filehandle in a list context which produces the list which it iterates over. Another thing to be aware of is that if you're iterating over a filehandle in a `while` loop perl will auto-magically stick a `defined` test around your condition e.g `while(my $line = <DATA>) # becomes while (defined(my $line = <DATA>))` [download] So now if a single 0 is read the loop will continue. HTH `_________ broquaint`	[reply] [d/l]

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Re: Re: Re: Trying to read a filehandle inside a loop
by broquaint (Abbot) on Oct 23, 2002 at 09:42 UTC

Why doesn't the 'while' loop slurp the data too?

foreach

while

defined

while(my $line = <DATA>)
# becomes
while (defined(my $line = <DATA>))
[download]

_________ broquaint

[reply]
[d/l]