Checking Regular Expression Syntax
November 18, 2003
If your program accepts a regular expression pattern, either from a user input or another module, you need to check that the pattern you receive is valid or not. To check for a valid pattern, apply the pattern against an empty string and wrap the expression in an eval.
sub my_func { my ($pattern) = @_; eval { "" =~ $pattern; }; if ($@) { die "Something wrong with your pattern: $pattern"; } # Otherwise, pattern is good and use it here. }