Extract substrings from string (parsing expression to get all tag references within)

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1

I'm using system.tag.getConfiguration() to get the expression out of an expression tag. From this, I want to extract a list of all the tags referenced in the expression. For example, if the expression is

{[.]../FolderA/Tag1}||{[.]../Tag2}||{[.]../FolderB/FolderC/Tag3}

I would like to return

{"[.]../FolderA/Tag1","[.]../Tag2","[.]../FolderB/FolderC/Tag3"}

I was hoping to find a script function that would search a string using regex to find a substring match, but I'm not seeing anything comparable to the IndexOf expression function.

Any recommendations on how to do this?

2

Searching "regex to find substrings enclosed in special characters" on google, the first result is this:

Replace their characters with yours and you should be okay.

edit: meh. This regex is a bit too specific to the user's case. Should have read BEFORE replying.
I'll try to make it work

edit2:
maybe this ?
re.findall(r"\{[^}]*\}", s)

  • \{ matches the opening {
  • [^}]* matches everything until the closing }
  • \} matches the closing '}'

if you want to make sure there's a provider: re.findall(r"\{\[[^]]*\][^}]*\}", s)

edit3:
actually... something like this ?
re.findall(r"(?<={)[^}]*", s)

  • (?<={) selects things AFTER the opening {
  • [^}]* selects everything up to the closing }

This way the {} are not included in the results

3

I group the look-aheads and look-behinds. To me, anyway, the pattern is more readable.

import re
        
regex = r"(?<={)(.*?)(?=})"

test_str = "{[.]../FolderA/Tag1}||{[.]../Tag2}||{[.]../FolderB/FolderC/Tag3}"

matches = re.findall(regex, test_str, re.MULTILINE)

print matches

Output:

['[.]../FolderA/Tag1', '[.]../Tag2', '[.]../FolderB/FolderC/Tag3']
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4

Just use Java's String.split()

I find that it's easier if you include the delimiters, that way you can eliminate any expressions that might be between tags.

I assume from your expected output that you were wanting a set, which would eliminate duplicate tag entries. A list could just as easily be used.

There is a java.util.StringTokenizer which will do this same thing, however, that has been deprecated. The recommended method is now String.split()

from java.lang import String

test = "{[.]../FolderA/Tag1}||{[.]../Tag2}||{[.]../FolderB/FolderC/Tag3}"

tokens = String(test).split("((?=\{|\})|(?<=\{|\}))")

tags = set()
enumToken = enumerate(tokens)

for cursor,token in enumToken:
	if token == "{":
		#start of tag path, consume the token
		cursor,token = next(enumToken)
		tags.add(token)
		
		#consume the ending brace
		cursor,token = next(enumToken)

print tags

output:

>>> 
set([u'[.]../Tag2', u'[.]../FolderA/Tag1', u'[.]../FolderB/FolderC/Tag3'])
>>>
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