Python re module FindAll () detailed

Writing code today, when writing to Zhengze, encountered a pit, which is the FindAll () function under the RE module.

Below I will combine the code to record

Importrestring="ABCDEFG acbdgef ABCDGFE cadbgfe"#the difference between parentheses and without parentheses#with no parenthesesRegex=re.compile ("((\w+) \s+\w+)")Print(Regex.findall (string))#output: [(' ABCDEFG acbdgef ', ' ABCDEFG '), (' Abcdgfe cadbgfe ', ' ABCDGFE ')]regex1=re.compile ("(\w+) \s+\w+")Print(Regex1.findall (string))#output: [' ABCDEFG ', ' ABCDGFE ']Regex2=re.compile ("\w+\s+\w+")Print(Regex2.findall (string))#output: [' ABCDEFG acbdgef ', ' Abcdgfe cadbgfe ']

With 2 parentheses in the first regex, we can see that its output is a list containing 2 tuple

The second regex has 1 parentheses, and the output is what the parentheses match, not the result that the entire expression matches.

The third regex does not have parentheses, and its output is what the entire expression matches.

Conclusion: FindAll () Returns the result that the parentheses match (for example, regex1), and multiple parentheses return the result (such as a regex) where the parentheses match, or return the entire statement (such as REGEX2) if no parentheses are returned. So when extracting the data, you need to pay attention to this pit.

Python re module FindAll () detailed