Also, you could use a regex to do this. As well, you could add the 'i' modifier to the regex if you wish to allow case-insensitivity, to allow such things as 'Red', 'GrEeN', 'BLUe':

if ($color =~ /\A(?:red|blue|green)\z/) {
 # do something here
}
[download]

Update: Fixed code to use \A and \z as mentioned below by Juerd and merlyn. I still haven't shaken the habit of using the nasty ^ and $ anchors. I also don't like the use of the /s modifier much, so I had best get used to the better-used anchors.

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