I'm back again..
in prior topics I discussed a section of my code that allows my users to execute an arbitrary regular expression using
eval $w;
where $w contains the expression..
but, if they code it wrong, my application dies.
for example, expression= '/HOST=.*('
will yield a fatal die error..
Unmatched ( in regex; marked by <-- HERE in
but I don't want it to be fatal..
the contents of $w is (no quotes)
'$expdata =~ /HOST=.*(;'
but eval {$w;} is ignored
--- from the perl content on eval
eval '$x'; # CASE 3
eval { $x }; # CASE 4
Cases 3 and 4 likewise behave in the same way: they run the code '$x', which does nothing but return the value of $x.
---
and I can confirm that the expression itself does not execute.
So.. is there some trick to this?
thanks
Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
Read Where should I post X? if you're not absolutely sure you're posting in the right place.
Please read these before you post! —
Posts may use any of the Perl Monks Approved HTML tags:
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
| |
For: |
|
Use: |
| & | | & |
| < | | < |
| > | | > |
| [ | | [ |
| ] | | ] |
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.