multiple replacements

[David Goodger]

on 2000-06-27 08:47, siva1311 at my-deja.com (siva1311 at my-deja.com) wrote:
> I am a newbie Python programmer and was wondering the best way to make
> multiple replacements of text strings in a file.

Perhaps a bit complex for a newbie, but the most definitive answer I've seen
so far has been Fredrik Lundh's 2000-04-12 reply to the "Python idiom:
Multiple search-and-replace" thread:

=============== forward ================

Randall Hopper <aa8vb at yahoo.com> wrote:
> Is there a Python feature or standard library API that will get me less
> Python code spinning inside this loop?   re.multisub or equivalent? :-)

haven't benchmarked it, but I suspect that this approach
is more efficient:

...

# based on re-example-5.py

import re
import string

symbol_map = { "foo": "FOO", "bar": "BAR" }

def symbol_replace(match, get=symbol_map.get):
    return get(match.group(1), "")

symbol_pattern = re.compile(
    "(" + string.join(map(re.escape, symbol_map.keys()), "|") + ")"
    )

print symbol_pattern.sub(symbol_replace, "foobarfiebarfoo")

...

</F>

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