question on perl's split function

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

monks,

#!/usr/bin/perl

my $string = "///a/b////c";

my @arr = split("\/*",$string);

print ":" , join("_",@arr) , ":\n";


Output :-
:_a_b_c:
[download]

but I want the out put as ":a_b_c:", I changed the join as

print ":" , join("_",@arr[1..$#arr]) , ":\n";
[download]

But in the above join explicitly I am removing the 0 index from the array to avoid. Is there a standard way to chop this null string in split function itself.

Comment on question on perl's split function Select or Download Code

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Re: question on perl's split function by GrandFather (Saint) on Oct 22, 2007 at 09:31 UTC
The leading string of /'s generates an empty first element. One fix is: `my @arr = grep {length} split("/+",$string);` [download] Perl is environmentally friendly - it saves trees	[reply] [d/l]
Re: question on perl's split function by moritz (Cardinal) on Oct 22, 2007 at 09:23 UTC
Unrelated to the rest of your question: chances are that the split doesn't do what you want it to, because it splits at the empty string. Try this instead: `my @arr = split m{/+}, $string;`	[reply] [d/l]
Re: question on perl's split function by rminner (Chaplain) on Oct 22, 2007 at 09:27 UTC
if you only want the none empty strings, then you can achieve it like this: `my $string = "///a/b////c"; my @arr = grep {$_ ne ''} split("\/+",$string); print ":" , join("_",@arr) , ":\n";` [download] Also: moritz is right, that /* matches 0 or more slashes, so it would also split the string where you wouldn't expect it to split the string. Simply try using the following string with your split regex of /*: `my $string = "//foo//bar///";` [download] then you'll understand the problem. + is what you need as it matches 1..n ocurrences of the previous char.	[reply] [d/l] [select]
Re: question on perl's split function by Prof Vince (Friar) on Oct 22, 2007 at 10:00 UTC
You can also use a regexp : `my @arr = $string =~ m,([^/]+),g;` Please note that Perl's split isn't PHP's and expects a pattern (or `' '`) as its first argument, so you'd better not split on a string if you don't know what's happening there.	[reply] [d/l] [select]