regex matches more than I want

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

I have data like .... in multiline string $lines

___DATA___
#Pattern 1 - aaa <anything> bbb <anything> ccc <whitespaces> dddd
aaa
 xxxxxxx
 bbb
    ccc
dddd
-------------------------------------
# Pattern 2 - aaa <anything> bbb <anything> ccc <whitespaces> dddd
aaa
    xxxxxxxxxxxxxxxxxxxxx
    xxxxxxx
  bbb
    xxxxxxxxxxxxxxxxxxxxx
    xxxx
    xx
ccc
dddd
[download]

I want

print  $#{[$lines =~ /aaa.*bbb.*ccc\s*dddd/gsi]} + 1 . "\n";
[download]

to give me 2. But it gives me 1. I assume that the culprut is .* Any way to get around this?

Comment on regex matches more than I want Select or Download Code

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Re: regex matches more than I want by duff (Parson) on Dec 02, 2003 at 14:38 UTC
The easiest way is to change your `.` to be an appropriate negated character class or to use the `?` modifier on the greedy `` to make it less greedy. `print $#{[$lines =~ /aaa[^b]bbb[^c]ccc\sdddd/gsi]} + 1 . "\n"; # or ...` `print $#{[$lines =~ /aaa.?bbb.?ccc\sdddd/gsi]} + 1 . "\n";` See the documentation in perlre and perlrequick and perlretut PerlJam	[reply] [d/l] [select]
Re: Re: regex matches more than I want by Anonymous Monk on Dec 03, 2003 at 06:36 UTC
Thanks guys for all the help !!!	[reply]
Re: regex matches more than I want by ChrisR (Hermit) on Dec 02, 2003 at 13:44 UTC
`.` is very greedy. Try this instead: `print $#{[$lines =~ /aaa(.?)bbb(.?)ccc\sdddd/gsi]} + 1 . "\n";` [download] Update: I went under the assumption that: `$lines = "aaa xxxxxxx bbb ccc dddd";` [download] `print $#{[$lines =~ /aaa(.?)bbb(.?)ccc\sdddd/gsi]} + 1 . "\n";` will return 2. If `$lines = " aaa xxxxxxx bbb ccc dddd aaa xxxxxxxxxxxxxxxxxxxxx xxxxxxx bbb xxxxxxxxxxxxxxxxxxxxx xxxx xx ccc dddd";` [download] `print $#{[$lines =~ /aaa(.?)bbb(.?)ccc\sdddd/gsi]} + 1 . "\n";` will return 4. If you use `$lines = " aaa xxxxxxx bbb ccc dddd aaa xxxxxxxxxxxxxxxxxxxxx xxxxxxx bbb xxxxxxxxxxxxxxxxxxxxx xxxx xx ccc dddd"; print $#{[$lines =~ /aaa.?bbb.?ccc\s*dddd/gsi]} + 1 . "\n";` [download] It will return 2. I'm not sure if thes helps or not but my guess is the last solution I show is what you want.	[reply] [d/l] [select]