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POHow do I match none, one or two value in one string?
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  1. POHow do I match none, one or two value in one string?
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    copied!<p>I have a string which can include none, one or two values. In case there are two value they are separated by a colon <code>:</code>, also if the first value should be empty the second (only value) would be prefixed by with a colon.</p> <p>The first value can be composed of pretty any character alphanumeric and special characters, the second value only of alphanumeric characters. Therefore a colon is not a distinct separator.</p> <p>I tried some regular expression, most of them work fine for only one value, or two values without a colon in the first but if the first one is empty the regex returns the whole string as first value.</p> <p>My actual code looks like:</p> <pre><code>if ($string =~ m/^(.+)(\:(\w+)|)$/){ $value1 = $1 || ''; if ($3){$value2 = $3} } </code></pre> <p>This one works for empty string, only first value, two values without colon in first value.</p> <p><strong>Edit</strong>:</p> <p>String could be:</p> <ul> <li><code>Hello World!</code> (only one value: value1='Hello World!')</li> <li><code>This is a test:123</code> (two values: value1='This is a test' value2='123')</li> <li><code>:Banana</code> (only one value: value2='Banana')</li> <li><code>T3-76:</code> (only one value: value1='T3-76:')</li> <li><code>Book:Title:Mysql</code> (two values: value1='Book:Title' value2='Mysql')</li> </ul> <p>The main problem is how to make a difference between a one value string which includes a colon <strong>and</strong> some text after the colon and a two values string with no colon in the first value. I should probably assume that if this case happen it is a two value string.</p> <p><strong>Edit2</strong></p> <p>If it makes it easier the code could be modified to <strong>not</strong> match an empty string.</p> <p>Anyone got an idea?</p>
 

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