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

Hi, I am new to perl and need a help with assigning $_ variable to a array within a foreach loop.when i try this following code foreach(@word){ @wordlwr = lc($_); } it only has the last value. any help?

Replies are listed 'Best First'.
Re: need help with array
by jbrugger (Parson) on Jul 18, 2005 at 07:54 UTC
    push @wordlwr, lc($_);
    "We all agree on the necessity of compromise. We just can't agree on when it's necessary to compromise." - Larry Wall.
[reply]
[d/l]
Re: need help with array
by eyepopslikeamosquito (Archbishop) on Jul 18, 2005 at 08:11 UTC

    Or: 

    my @wordlwr = map { lc($_) } @word;

    [download]

[reply]
[d/l]
[reply]
[d/l]
        or one character less:

        my @wordlwr = map lc, @word;

        [download]

        since map can take an expression or a block as it's first argument... now i'll take a bow for the lamest golf ever...
[reply]
[d/l]
Re: need help with array
by AReed (Pilgrim) on Jul 18, 2005 at 13:37 UTC
    The foreach loop aliases each element of the array to a loop variable for each iteration. If you don't include a loop variable explicitly, perl uses $_ by default.

    The problem with your original code is that each iteration of the loop replaces the contents of your @wordlwr array with the current contents of $_ instead of appending $_ to the array as you expect. I think that the following code is what you want. 

    use strict;

my @words = qw/ONE TWO THREE/;
my @wordlwr = ();

foreach (@words) {
    push @wordlwr, lc($_);
}

foreach (@wordlwr) {
    print "$_\n";
}

    [download]
[reply]
[d/l]
Re: need help with array
by ghenry (Vicar) on Jul 18, 2005 at 08:53 UTC

    Using foreach in simple terms using simple language, in case you don't understand the above:

    use warnings;
use strict;
my @word = qw/ ONE TWO THREE FOUR/;
foreach my $lcword (@word) {
    $lcword = lc($lcword);
}
print "@word";

    [download]

    HTH.

    Walking the road to enlightenment... I found a penguin and a camel on the way.....
    Fancy a yourname@perl.me.uk? Just ask!!!
[reply]
[d/l]
      Your code does not use a second array as it is the question of the OP. And it does use the aliasing mechanism of the foreach loop. Maybe you should have mentioned that? I mean, it confuses me from time to time. How is it for a newbie?


      holli, /regexed monk/
[reply]
[d/l]

Back to Seekers of Perl Wisdom