Validation of user provided regex

[Gunnar Hjalmarsson]

In an app where a user may provide a Perl regular expression I want to
validate the regex before it's applied. Currently I'm doing something like:

{
local $SIG{__WARN__} = sub { die $_[0] };
eval { $regex = qr($regex) };
die $@ if $@;
}

In other words I rely on Perl's ability to catch errors, where also
warnings are treated as errors.

Are there other appropriate checks that could be done?

 

[anno4000]

In an app where a user may provide a Perl regular expression I want to
validate the regex before it's applied. Currently I'm doing something like:

{
local $SIG{__WARN__} = sub { die $_[0] };
eval { $regex = qr($regex) };
die $@ if $@;
}

In other words I rely on Perl's ability to catch errors, where also
warnings are treated as errors.

Are there other appropriate checks that could be done?

If code interpolations are a possibility, you may want to "use re
'eval';" in the block. Or not, depending...

Anno

 

[Gunnar Hjalmarsson]

In an app where a user may provide a Perl regular expression I want to
validate the regex before it's applied. Currently I'm doing something like:

{
local $SIG{__WARN__} = sub { die $_[0] };
eval { $regex = qr($regex) };
die $@ if $@;
}

In other words I rely on Perl's ability to catch errors, where also
warnings are treated as errors.

Are there other appropriate checks that could be done?

If code interpolations are a possibility, you may want to "use re
'eval';" in the block. Or not, depending...

Thanks for the tip, but I really don't see a need for using (?{ ... }),
so I guess I'd better not.