Insanity

[Fredrik Lundh]

Tim Daneliuk wrote:

> Given an arbitrary string, I want to find each individual instance of
> text in the form:  "[PROMPT:optional text]"
>
> I tried this:
>
>     y=re.compile(r'\[PROMPT:.*\]')
>
> Which works fine when the text is exactly "[PROMPT:whatever]"

didn't you leave something out here?  "compile" only compiles that pattern;
it doesn't match it against your string...

> but does not match on:
>
>    "something [PROMPT:foo] something [PROMPT:bar] something ..."
>
> The overall goal is to identify the beginning and end of each [PROMPT...]
> string in the line.

if the pattern can occur anywhere in the string, you need to use "search",
not "match".  if you want multiple matches, you can use "findall" or, better
in this case, "finditer":

import re

s = "something [PROMPT:foo] something [PROMPT:bar] something"

for m in re.finditer(r'\[PROMPT:[^]]*\]', s):
    print m.span(0)

prints

    (10, 22)
    (33, 45)

which looks reasonably correct.

(note the "[^x]*x" form, which is an efficient way to spell "non-greedy match"
for cases like this)

</F>