You should recommend people avoid constructs like: [Jj][Aa][Vv][Aa] as they are quite inefficient and also can blow out various optimizations just by their presence. Its better to write that (?i:Java). Also up until 5.9.2 perl doesnt optimise alternations very well so its advisable to use modules like Regexp::List or the like to preprocess
. OTOH as of 5.9.2 perl _does_ optimize them so using things like Regexp::List
will only slow down your patterns (im hopeful by 5.10 these modules will be updated to Do The Right Thing Regardless™).
In fact if at all possible after that version it is recommended that you use alternations instead of using quantifier, bracketing. Ie,
will be more efficent that
as of 5.9.2, and in some circumstance massively more efficient.
I admit i wrote the optimization so im tooting my own horn here a bit. :-) But it is worth realizing that alternations in later perls can be signifigantly faster than other hypothetically equivelent patterns.
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:
You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
- a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, 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, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
Link using PerlMonks shortcuts! What shortcuts can I use for linking?
See Writeup Formatting Tips and other pages linked from there for more info.
| & || & |
| < || < |
| > || > |
| [ || [ |
| ] || ] ||