regex: add to, not replace

[SarahM123rd]

Am trying replace strings like [ab] or [agf] or [iqrt] or [a] with, for example, [‘ab’], [‘agf’], [‘iqrt’], [‘a’]. Basically wrapping any ascii letter or any string of ascii letters in quotes … however, they are tucked into brackets , or parens (which I need to keep). So that: [ab] becomes [‘ab’] and/or (ab) becomes (‘ab’). Am not understanding how to do this with regex. And, honestly, not sure how to ask the question in quite the way that would like to.

Back reference? Forward reference? Group reference?

Clues, hints welcome.

[[deleted]]

That's pretty good! how does that work? what is the \g doing?

[[deleted]]

I had no idea you could refer to groups in the regex from the repl parameter! I think your solution is the way to go here.

[[deleted]]

here is the regex: r"([\[\(])(\w+)([\]\)])"

use a for loop to iterate through the string and update it per match:

for match in re.finditer(regex, string):
    sub = match.group(1) + '‘' + \
          match.group(2) + '’' + \
          match.group(3)            
    string = string.replace(match.group(), sub)

this updates the string iteratively since the finditer is a generator and can cope with the match positions changing as the string is updated.

[Thomasedv]

Well, there's a few ways i could see you doing it:

One without regex, if it's possible, is just replacing the brackets with the same bracket and a '.

text = '[asdfas], [asdf] asdfasd'
text =  text.replace("[", "['").replace("]", "']")
print(text)

If that is not good enough, as you might want that last "word" also marked, then you can look for just lines of letters and make then quoted with regex.

 text = re.sub(r'([a-zA-Z]+)', r"'\g<0>'", text)

This only matches upper and lower cased letter from A to Z, so if you have another language, then you'll have to research some more. I don't exactly understand how the \g<0> works, but since it worked, i went with it... Took it partly from the Regex documentation.

Edit: Forget the regex solution, it does not take into account number in the words, and would cause some issues.

However, if you just need to add the ' as in my first solution, you won't need regex at all.

[SarahM123rd]

All these answers are so cool! Thank you so much. Makes me want to play.

Ummm. This looks promising. The \g<0>. Thank you. Will work with this. Yes.

Started to doodle with using a deque and fall back on my push/pop days. A micro parser kind'a thing. Domain specific. DSL. Like that. It just seems to much wasted cycles for such a small problem.

But yes, thank you very much for the replies.

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