Delete one by one the elements of a list, and then restore the previous ones-CodePudding

I need it to extract the word that starts with a capital letter, if and only if, this word is preceded by the beginning of the sentence or by one of these options (?:,and|and|her friends|,or |or |,)

import re

match_names = ""

input_sense = "Susan gave some cosmetic gifts to her friends Lisa, Veronica and Katy, but only Katy thanked her"

#I concatenate a series of characters that probably nobody uses so that it searches at the beginning
input_sense = "rlt99ll"   input_sense

if match := re.findall(r"(?:rlt99ll|,and|and|her friends|,or |or |,)\s*([A-Z].*?\b)", input_sense):
    match_names = match
    print("match names: ")
    print(match_names)

input_sense = input_sense.replace("rlt99ll", "") #I add this aux-string only for the pattern

n = 0
print("match_auxs : ")
for name in match_names:
    match_aux = match_names

    for m in match_aux:
        if (m == name):
            match_aux[n] = ""
        n  = 1

    n = 0
    print(match_aux)

I need that output lists:

match names: 
['Susan', 'Lisa', 'Veronica', 'Katy']
match_auxs : 
['','Lisa', 'Veronica', 'Katy']
['Susan', '', 'Veronica', 'Katy']
['Susan', 'Lisa', '', 'Katy']
['Susan', 'Lisa', 'Veronica', '']

But I get this ( and it's wrong)...

match names: 
['Susan', 'Lisa', 'Veronica', 'Katy']
match_auxs : 
['', 'Lisa', 'Veronica', 'Katy']
['', '', 'Veronica', 'Katy']
['', '', '', 'Katy']
['', '', '', '']

CodePudding user response：

As said in the comments, assigning a list to another variable doesn't create a copy of it. Along with this, your code can be simplified by using functions like enumerate:

import re

match_names = ""

input_sense = "Susan gave some cosmetic gifts to her friends Lisa, Veronica and Katy, but only Katy thanked her"

#I concatenate a series of characters that probably nobody uses so that it searches at the beginning
input_sense = "rlt99ll"   input_sense

if match_names := re.findall(r"(?:rlt99ll|,and|and|her friends|,or |or |,)\s*([A-Z].*?\b)", input_sense):
    print(f"match names: {match_names}")

input_sense = input_sense.replace("rlt99ll", "") #I add this aux-string only for the pattern

n = 0
print("match_auxs: ")
for index, name in enumerate(match_names):
    match_aux = match_names.copy()
    match_aux[index] = ""
    n = 0

    print(match_aux)

If you don't want to use copy on the list (for speed), this code will also work:

import re

match_names = ""

input_sense = "Susan gave some cosmetic gifts to her friends Lisa, Veronica and Katy, but only Katy thanked her"

#I concatenate a series of characters that probably nobody uses so that it searches at the beginning
input_sense = "rlt99ll"   input_sense

if match_names := re.findall(r"(?:rlt99ll|,and|and|her friends|,or |or |,)\s*([A-Z].*?\b)", input_sense):
    print(f"match names: {match_names}")

input_sense = input_sense.replace("rlt99ll", "") #I add this aux-string only for the pattern

n = 0
print("match_auxs: ")
prev = ""
for index, name in enumerate(match_names):
    if index > 0:
        match_names[index - 1] = prev
    prev = match_names[index]
    match_names[index] = ""

    print(match_names)
match_names[-1] = prev