Lie Ryan wrote:
Why am I seeing a lot of this pattern lately:
OP: Got problem with string
+- A: Suggested a regex-based solution
+- B: Quoted "Some people ... regex ... two problems."
or
OP: Writes some regex, found problem
+- A: Quoted "Some people ... regex ... two problems."
+- B: Supplied regex-based solution, clean one
+- A: Suggested PyParsing (or similar)
There's a spectrum of parsing solutions:
- string.split() or string[slice] notations handle simple cases
and are built-in
- regexps handle more complex parsing tasks and are also built in
- pyparsing handles far more complex parsing tasks (nesting, etc)
but isn't built-in
The above dialog tends to appear when the task isn't in the
sweet-spot of regexps. Either it's sufficiently simple that
simple split/slice notation will do, or (at the other end of the
spectrum) the effort to get it working with a regexp is hairy and
convoluted, worthy of a more readable solution implemented with
pyparsing. The problem comes from people thinking that regexps
are the right solution to *every* problem...often demonstrated by
the OP writing "how do I write a regexp to solve this
<non-regexp-optimal> problem" assuming regexps are the right tool
for everything.
There are some problem-classes for which regexps are the *right*
solution, and I don't see as much of your example dialog in those
cases.
-tkc
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