Trouble with m///g

From: Chap Harrison (clh_at_pobox.com)
Date: 09/30/04 

To: beginners@perl.org
Date: Thu, 30 Sep 2004 09:37:55 -0500

Hi,

I'm trying to extract all four-digit numbers from a string in one fell
swoop, but I can't seem to come up with the proper regexp. This is my
first time using /g in a match so maybe there's a trick I'm missing.

For example, the string

"1111 2222aa3333 444 55555555 6666 7777-8888"

should yield

1111, 2222, 3333, 6666, 7777, 8888.

Here's one attempt that I thought had a reasonable chance.

- - - - -
#!/usr/bin/perl -w
my $foo = "1111 2222aa3333 444 55555555 6666 7777-8888";
my @a = ($foo =~ m'[\D^](\d{4})[\D$]'g);
print "<$foo>\n";
print(join(":",@a)."\n");
- - - - -

<1111 2222aa3333 444 55555555 6666 7777-8888>
2222:3333:6666

Thanks for your consideration,
Chap

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  • RE: Trouble with m///g
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