 | View Full Version : regex matching a pseudo-code if, then, else construct koorb 11-16-2003, 10:13 AM What pattern would i use to match a string like {if condition} <html> {else} <other html> {endif} where the {else} <other html> is optional, can I do this with just one pattern John[H4Y] 11-16-2003, 12:35 PM I assume you are talking about doing one thing if you match <html>, another if you match <any other tag>. I might have totally misinterpretted your post.. if so, let me know. in perl: $html = "some html"; if ($html =~ m/<html>/i) { &dosomething; } elsif ($html =~ m/<[^<>]*>/) { &dosomethingelse; } in php: <?php $html = "some html"; if (eregi("<html>", $html)) { dosomething(); } elseif (ereg("<[^<>]*>", $html)) { dosomethingelse(); } ?> If there is a tag in $html with anything but <html>, it will perform the dosomethingelse function, but with no match it would just continue executing without executing dosomething() or dosomethingelse(). If I didn't understand what you were asking and you were referring to actually matching the phrase: "{if condition} <html> {else} <other html> {endif}", the only problem is I don't know what type of input you are expecting exactly (are you trying to match "if condition" literally or would the "codition" part change)? Please provide more details. koorb 11-16-2003, 04:23 PM i will try to explain better, I am creating a faily simple template system and want to be able to use some basic control structures in the templates. Literaly in the template file <html> .. html stuff {if condition} .. do this stuff ... {else} .. do this stuff ... {endif} ..more html things... </html> // eof so I need to (in php) match the {if} statements extracting the `condition` to evaluate and each `.. do this stuff ...` to do if the condition is true or false. I have got it basicly but i cannot have any other {} template code in bettween. the pattern i am using at the moment is: /\{if([^\r\n\}\{]+)\}([^\{\}]+)(?:\{else\}([^\{\}]+))?\{\/if\}/ if you can read through that :D basicly matching {if any character that isnt a new line or return} any character that isnt { or } //optionaly// {/else} any character that isnt { or } //optionaly// {/if} any help in getting this to work better would be good, i want to be able to use other { } structures within each other. Same situation with {loop array} ..loop this stuff.. {/loop} works but cant have any other { } `tags` in bettween Burhan 11-16-2003, 05:18 PM Smarty (http://smarty.php.net) does what you want (with a smiliar tag syntax). Trying to reinvent the wheel? :D koorb 11-16-2003, 07:04 PM to put it simply smarty is too big :D Im not doing anything major, im just realy anal about doing things myself (he says having just used the phpmailer class :D) no but i have looked for an appropriate template class, what i have will do, i wasnt after to advanced template coding so i think i will be ok, I got kinda caried away :D hiryuu 11-16-2003, 11:45 PM If GPL code is okay with you, I would suggest dissecting smarty and pulling what you need. I have this sinking feeling it looks more like a compiler than a regex. That probably explains a lot about its size. |