How can I check if a regex pattern is valid in Perl?
perl, regex
Solution
I am no Perl expert, but maybe this can help:
#!/usr/bin/perl
my $pattern = "["; # <-insert your pattern here
my $regex = eval { qr/$pattern/ };
die "invalid regex: $@" if $@;
which returns this:
invalid regex: Unmatched [ in regex; marked by <-- HERE in m/[ <-- HERE / at test.pl line 4.
For your second question you could always check out the huge body of work at CPAN.
Problem
Firstly, I was wondering if there was some kind of built in function that would check to see if a regex pattern was valid or not. I don't want to check to see if the expression works - I simply want to check it to make sure that the syntax of the pattern is valid - if that's possible. If there is no built in function to do so, how do I do it on my own? Do I even need to? Is there a directory of built in functions/modules that I can search so I can avoid more questions like this? Thank you. EDIT: I should mention that I plan on generating these patterns on the fly based on user input - which is why I'd like to validate them to make sure they will actually run.