PyParsing: how to parse a function call and returning it as string

Question

From here I have this code to parse a function call:

functionName = Word(alphanums + '_')
functionBody = Forward()
functionBody <<= functionName + (Literal("(") + Optional( delimitedList ( functionBody | Word(alphanums + '_') | "''"),'') + Literal(")"))

But, when calling:

result = functionBody.parseString('function(param1,param2,param3)')

I got this result:

['function', '(', 'param1', 'param2', 'param3', ')']

Is there any way to get this result instead:

['function(param1, param2, param3)']

That is to say: parsing the function call is well written, but returning it as string instead of as an array without using the Python join sentence?

"...without using the Python join sentence?" and why is that? I believe that is the best way. — Jaideep Shekhar, Jan 13 '20 at 13:18
@JaideepShekhar, I am using this code snippet within another expression, and pyparsing returns me nothing but errors if I don't call it as string. — assembler, Jan 13 '20 at 13:26
You have 3 options for this: `originalTextFor`, `Combine`, or `function_body.addParseAction(''.join)`. Do some experimenting with these, and see which you like the best. — PaulMcG, Jan 13 '20 at 21:53

score 0 · Accepted Answer · answered Jan 14 '20 at 13:47

I thank Mr. PaulMcG, since he gave three possible answers in his comment, but I am posting a solution for somebody who might be needing it as well. originalTextFor did the trick for me:

functionName = Word(alphanums + '_')
functionBody = Forward()
functionBody <<= originalTextFor(functionName + (Literal("(") + Optional( delimitedList ( functionBody | Word(alphanums + '_') | "''"),'') + Literal(")")))

Now it is returning:

['function(param1,param2,param3)']

PyParsing: how to parse a function call and returning it as string

1 Answers1