On Nov 17, angie ahl said:
>I keep getting hung up on deciding whether to use for or while for
>loops.
Well, it usually depends on how the code "reads". I use 'while' for loops
based on a condition that will change in some execution of the block.
while (<FILE>) {
# eventually, <FILE> will return undef when the file is exhausted
}
while ($i < 5) {
# $i will be changed somehow
# eventually it will be greater than or equal to 5
}
while ($x or $y or $z) {
# continue while one of those three variables is still true
}
It's important to note that
while (<FILE>) { ... }
is identical to
while (defined($_ = <FILE>)) { ... }
which only reads ONE line at a time, whereas
for (<FILE>) { ... }
reads ALL the lines of the file at once, into a list.
A for loop is best used for iterating over a list of values, or, in the
C-style loop, running through a range.
--
Jeff "japhy" Pinyan [EMAIL PROTECTED] http://www.pobox.com/~japhy/
RPI Acacia brother #734 http://www.perlmonks.org/ http://www.cpan.org/
<stu> what does y/// stand for? <tenderpuss> why, yansliterate of course.
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