All:
While trying to come up with a good solution for a problem EdwardG presented, I needed to find a way of skipping entries where the first letter of one string did not match the first letter of a second string. An "expensive" function had to be called, so I wanted to disqualify impossible candidates first.

What are some other ways you can think of to do: 

my $str_a = 'Foo';                                # Can be any length
for my $str_b ( @list ) {                         # Can be any number 
+of items
    next if index($str_a, substr($str_b, 0, 1));  # Only change this
    expensive_function($str_a , $str_b);
}

[download]

Without much effort, I can think of 3 other ways of doing this.

I will benchmark all the solutions to see which is the fastest. If you suspect your solution will work well in certain situations, but not well in others feel free to state as much. I am even interested to see if merlyn provides an Inline::C solution. While I am looking for speed, creative solutions will get honorable mentions.

Cheers - L~R

In reply to Matching First Character of Strings Efficiently by Limbic~Region

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