help with split()

kevinw has asked for the wisdom of the Perl Monks concerning the following question:

hi, i think i'm using the split() function right, but for some reason, it does not work out how i want....could someone please help? i have

while (<FILE>) {
    $class= split(/\s+/,$_);
    print $class;
}
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basically, FILE contains the following data and i want to get the classes which is the first column.....

Classes categorized by sections:

section 1
classC     18
classA     17
classD     16

section2
classE    15
classO    14
classB    16
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Re: help with split() by DamnDirtyApe (Curate) on Jul 25, 2002 at 21:36 UTC
You're close; `split` returns a list. You want something more like: `while (<FILE>) { ($class, $enrollment) = split(/\s+/,$_); print $class; }` [download] Update: Also, the `$_` is implied, so you can just write: `( $class, $enrollment ) = split /\s+/ ;` [download] _______________ D a m n D i r t y A p e Home Node \| Email	[reply] [d/l] [select]
Re: help with split() by dragonchild (Archbishop) on Jul 25, 2002 at 21:39 UTC
Context, context, context. split returns an array. When an array is put into scalar context, it gives the number of elements in the array, not the first value. `while (<FILE>) { ($class) = split /\s+/, $_; print $class, $/; }` [download] It will discard all the other elements. As an aside, check out strict and warnings. They'll help save your life sometime. ------ We are the carpenters and bricklayers of the Information Age. Don't go borrowing trouble. For programmers, this means Worry only about what you need to implement.	[reply] [d/l]
Re: help with split() by thelenm (Vicar) on Jul 25, 2002 at 21:44 UTC
The answers so far are right on. Also, if you're only interested in getting the first column, you don't need to use split; you could just use a regex to grab it: `while (<FILE>) { my ($class) = /(\S+)/; print "$class\n"; }` [download] -- Mike `-- just,my${.02}`	[reply] [d/l]