Matching Part of a String in a IF Statment

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

It's late and I can't get this to work for some reason.

I have two variables: $city and $cityState

$city = "Chicago";
$cityState = "Chicago, IL";
[download]

You can see that the $city variable is just a city name and the $cityState variable is the City with a comma and then the state.

How can I get this code to check to see if the Cities match?

The below code shouldn't match.

#!/usr/bin/perl

my $city = "Naperville";
my $cityState = "Chicago, IL";

if ( $cityState =~ /\$city+/) {
    print "They match!"; 
  } else {
    print "dont match";
  }
[download]

The below code should match.

#!/usr/bin/perl

my $city = "Chicago";
my $cityState = "Chicago, IL";

if ( $cityState =~ /\$city+/) {
    print "They match!"; 
  } else {
    print "dont match";
  }
[download]

Comment on Matching Part of a String in a IF Statment Select or Download Code

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Re: Matching Part of a String in a IF Statment by Corion (Patriarch) on Dec 12, 2005 at 08:53 UTC
You're quoting the dollar sign of `$city` when you want `$city` to be interpolated. Perl knows when dollar is meant to mean "end-of-string" and when it's meant to mean "begin of a scalar variable". You want the following: `#!/usr/bin/perl my $city = "Naperville"; my $cityState = "Chicago, IL"; if ( $cityState =~ /\b\Q$city\E\b/) { print "They match!"; } else { print "dont match"; }` [download] I've added `\Q..\E` modifiers, so you can have cities with "special" characters in their names, like `[]+*^` - I don't know if that's the case with your data but it's better to be safe than sorry. I also added word boundaries so `Naper` and `Naperville` are treated as two distinct towns.	[reply] [d/l] [select]
Re: Matching Part of a String in a IF Statment by murugu (Curate) on Dec 12, 2005 at 09:06 UTC
Hi awohld, Its not matching because, it's trying to match '$city' i.e $city doesn't get interpolated. Remove that \ before $city, then it will match. You should also add boundary condition \b to the expression so that the you can do exact string match. (i.e)substring matches can be avoided Regards, Murugesan Kandasamy use perl for(;;);	[reply]
Re^2: Matching Part of a String in a IF Statment by Fletch (Bishop) on Dec 12, 2005 at 14:57 UTC
Technically it's trying to match `$cit` followed by one or more of `y`</pedant>	[reply]