Hello Monks,

I am building a program which allows users to filter files based on a regular expression that they provide. I want to do some input validation to prevent the script from dying if they messed up on the RE.

My question is this: Is there a way to check the string they entered to verify it's a legitimate RE?

Once I have the RE, I will use File::Find to list files recursively. If a file matches their RE, I'll skip it.

One example of a problem I might run into is if they were to specify this as their RE:

/skipthis/file/

I thought maybe I could do it this way, but it doesn't test true if the string doesn't match their legitimate RE:

$RE = <their regular expression>
$Anytext = "test";
$Anytext =~ s/$RE// || print "This is not a valid RE.\n";

The problem here is that if $Anytext doesn't match the RE, it'll tell me the RE is invalid.

Any ideas?

Thank you,

Morpheous1129 (Sean McDaniel)

In reply to Input Validation - verifying a string is a properly formatted regular expression by morpheous1129

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