from pyparsing import * # first pass lbrack = Literal("[") rbrack = Literal("]") integer = Word(nums).setName("integer") real = Combine(Optional(oneOf("+ -")) + Word(nums) + "." + Optional(Word(nums))).setName("real") listItem = real | integer | quotedString listStr = lbrack + delimitedList(listItem) + rbrack test = "['a', 100, 3.14]" print listStr.parseString(test) # second pass, cleanup and add converters lbrack = Literal("[").suppress() rbrack = Literal("]").suppress() cvtInt = lambda s,l,toks: int(toks[0]) integer = Word(nums).setName("integer").setParseAction( cvtInt ) cvtReal = lambda s,l,toks: float(toks[0]) real = Combine(Optional(oneOf("+ -")) + Word(nums) + "." + Optional(Word(nums))).setName("real").setParseAction( cvtReal ) listItem = real | integer | quotedString.setParseAction( removeQuotes ) listStr = lbrack + delimitedList(listItem) + rbrack test = "['a', 100, 3.14]" print listStr.parseString(test) # third pass, add nested list support cvtInt = lambda s,l,toks: int(toks[0]) cvtReal = lambda s,l,toks: float(toks[0]) lbrack = Literal("[").suppress() rbrack = Literal("]").suppress() integer = Word(nums).setName("integer").setParseAction( cvtInt ) real = Combine(Optional(oneOf("+ -")) + Word(nums) + "." + Optional(Word(nums))).setName("real").setParseAction( cvtReal ) listStr = Forward() listItem = real | integer | quotedString.setParseAction(removeQuotes) | Group(listStr) listStr << lbrack + delimitedList(listItem) + rbrack test = "['a', 100, 3.14, [ +2.718, 'xyzzy', -1.414] ]" print listStr.parseString(test)