SPUG: passing in a reg exp as a string, then interpolating

[Dean Hudson]

This seems pretty dangerous in general; in particular without taint
checking. Depending on which version of perl you're running, you need
to be careful to watch out for things like:

(?{ evil code })

That being said, you can also play around with qr//, which would allow
you to pass options to your regex. (But I don't think you can pass
the opts in a valiable...)

See perlop and perlre, and be careful with what you do with the user
input.

dean.

On Fri, Jun 09, 2000 at 04:18:35PM -0400, Joel wrote:
> On Fri, 9 Jun 2000, Christopher Cavnor wrote:
> 
> > does anyone know how to pass a regular expression into a script (in my
> > case, from an HTML form) and then evaluate the expression?
> > 
> > I am passing in a reg exp (like "/^hello/ ")as a string and grabbing
> > it (my $regexp = /^hello/ ), and then trying to interpolate:
> > 
> > push @results, $k if do{ $k =~ @{[ $regexp ]};
> > 
> > Doesn't seem to be working. Any tricks for doing this?
> 
> 
> You could use 'eval': 
> 
> #!/usr/local/bin/perl
> 
> use strict;
> 
> my @results;
> my $regex = '/^hello/';
> my $test  = 'hello world';
> 
> push @results, $test if ( $test =~ eval $regex );
> 
> print "@results\n";  # prints "hello world\n";
> 
> __END__
> 
> 
> Joel
> 
> 
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