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exact pattern matching

hi,
i am very new to perl

how to give exact pattern matching
example:
i have the data as follows

mm100
mm100-m1
mm101
mm101-m1
mm101-m2


so, i should get only
mm100
mm101

or
mm100-m1
mm101-m1
mm101-m2


if i say =~/mm-/
i am retreiveing all the values
Give me the solution pls.....
Oct 15 '07 #1
2 1665
mehj123
55
hi,
i am very new to perl

how to give exact pattern matching
example:
i have the data as follows

mm100
mm100-m1
mm101
mm101-m1
mm101-m2


so, i should get only
mm100
mm101

or
mm100-m1
mm101-m1
mm101-m2


if i say =~/mm-/
i am retreiveing all the values
Give me the solution pls.....
If you are making an exact comparison you can use '^' at the beginning and '$' at end...
e.g.
Expand|Select|Wrap|Line Numbers
  1. $var =~ /^mm$/
'^' stands for beginning and '$' stands for end of the string..

But one doubt. If you want to do an exact comparison y cant you go simply for

Expand|Select|Wrap|Line Numbers
  1. $var eq 'mm' 
Oct 15 '07 #2
numberwhun
3,509 Expert Mod 2GB
hi,
i am very new to perl

how to give exact pattern matching
example:
i have the data as follows

mm100
mm100-m1
mm101
mm101-m1
mm101-m2


so, i should get only
mm100
mm101

or
mm100-m1
mm101-m1
mm101-m2


if i say =~/mm-/
i am retreiveing all the values
Give me the solution pls.....
You will definitely want to read up a little bit on your regular expressions as this is not really that difficult. To get just the mm100(or 101) minus the "-m1" or "-m2" try the following:

[code-perl]
$var =~ m/^(\w{2}\d{3})\-\w\d$/
[/code]

The encolsing ( ) around the first half of that can be referenced now as $1, which will contain that match.

Regards,

Jeff
Oct 15 '07 #3

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