How to extract a word from a string in python

Question

Im getting functions from a smart contract in this format I print them out in a loop:

allFunctions = contract.all_functions()
for text in allFunctions:
      print(text)

<Function approve(address,uint256)>
<Function balanceOf(address)>
<Function burn(uint256)>
<Function burnFrom(address,uint256)>
<Function decimals()>
<Function decreaseAllowance(address,uint256)>
<Function increaseAllowance(address,uint256)>
<Function mint(address,uint256)>
<Function name()>
<Function owner()>
<Function pause()>
<Function paused()>
<Function renounceOwnership()>
<Function symbol()>

Now I want to dynamically remove everything from this string so Im only left with the actual function name which is approve balanceOf,name, owner pause etc...

I need to do this manually since a lot of smart contracts have different function names

So I can not use strip("<function ()>") Any ideas on how I can solve this?

The ouptut type I get is

<class 'web3._utils.datatypes.allowance'>

what happens when you `print(type(text))` ? – warped Mar 08 '22 at 16:23 — warped, Mar 08 '22 at 16:23

score 0 · Answer 1 · answered Mar 08 '22 at 16:09

0

Split using space, take the second element, split using parenthesis and take the first element

text = "<Function approve(address,uint256)>"
print(text.split(" ")[1].split("(")[0])


approve

answered Mar 08 '22 at 16:09

I cant do this in a loop, it keeps saying text has no attribute split – Joe Blow Mar 08 '22 at 16:13

warped · Accepted Answer · 2022-03-08T17:05:05.967

0

Assuming all data in a string, you can use regex:

import re

a = '''<Function approve(address,uint256)>
<Function balanceOf(address)>
<Function burn(uint256)>
<Function burnFrom(address,uint256)>
<Function decimals()>
<Function decreaseAllowance(address,uint256)>
<Function increaseAllowance(address,uint256)>
<Function mint(address,uint256)>
<Function name()>
<Function owner()>
<Function pause()>
<Function paused()>
<Function renounceOwnership()>
<Function symbol()>'''

re.findall("Function (.*)\(.*\)", a)

edit:

import re

allFunctions = contract.all_functions()
for text in allFunctions:
      print(re.findall("Function (.*)\(.*\)", text.__str__())[0])

edited Mar 08 '22 at 17:05

answered Mar 08 '22 at 16:11

warped

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its not working – Joe Blow Mar 08 '22 at 16:19
@JoeBlow Edit yout question with the exact input and the output you want processed. As it is, what you posted is not valid python code, so it is difficult to help. – warped Mar 08 '22 at 16:21
I have posted the python code, I just loop over allFunctions and below is what I get after from print – Joe Blow Mar 08 '22 at 16:25
@JoeBlow try the edit? – warped Mar 08 '22 at 16:34
doesnt work either return _compile(pattern, flags).findall(string) TypeError: expected string or bytes-like object – Joe Blow Mar 08 '22 at 16:40
@JoeBlow now try with the extra parentheses? – warped Mar 08 '22 at 16:52
its better but I get this ['allowance'] ['approve'] ['balanceOf'] ['burn'] ['burnFrom'] ['decimals'] ['decreaseAllowance'] ['increaseAllowance'] ['mint'] ['name'] I need a string – Joe Blow Mar 08 '22 at 16:59
@JoeBlow you can get the first entry of the list that the regex outputs. See the edit – warped Mar 08 '22 at 17:05
thanks this did work actually – Joe Blow Mar 08 '22 at 17:08
What `contract` in the code (not defined)? – YasserKhalil Mar 23 '22 at 08:42
@YasserKhalil ask the person that asked the question. – warped Mar 23 '22 at 09:12

score 0 · Answer 3 · answered Mar 08 '22 at 16:12

0

You can use split:

txt = "<Function balanceOf(address)>"

txt.split()[1].split('(')[0]

answered Mar 08 '22 at 16:12

Luiz Viola

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that doesnt work – Joe Blow Mar 08 '22 at 16:19

3nws · Answer 4 · 2022-03-08T16:24:39.113

0

Something like this seems to work:

functions = [func[:-1] for func in "".join(allFunctions).split('<Function ')][1:]

edited Mar 08 '22 at 16:24

answered Mar 08 '22 at 16:12

3nws

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How to extract a word from a string in python

4 Answers4

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