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# parsePythonValue.py
#
# Copyright, 2006, by Paul McGuire
#
from __future__ import print_function
import pyparsing as pp
cvtBool = lambda t:t[0]=='True'
cvtInt = lambda toks: int(toks[0])
cvtReal = lambda toks: float(toks[0])
cvtTuple = lambda toks : tuple(toks.asList())
cvtDict = lambda toks: dict(toks.asList())
cvtList = lambda toks: [toks.asList()]
# define punctuation as suppressed literals
lparen, rparen, lbrack, rbrack, lbrace, rbrace, colon, comma = map(pp.Suppress,"()[]{}:,")
integer = pp.Regex(r"[+-]?\d+").setName("integer").setParseAction(cvtInt )
real = pp.Regex(r"[+-]?\d+\.\d*([Ee][+-]?\d+)?").setName("real").setParseAction(cvtReal)
tupleStr = pp.Forward()
listStr = pp.Forward()
dictStr = pp.Forward()
pp.unicodeString.setParseAction(lambda t:t[0][2:-1])
pp.quotedString.setParseAction(lambda t:t[0][1:-1])
boolLiteral = pp.oneOf("True False").setParseAction(cvtBool)
noneLiteral = pp.Literal("None").setParseAction(pp.replaceWith(None))
listItem = (real
| integer
| pp.quotedString
| pp.unicodeString
| boolLiteral
| noneLiteral
| pp.Group(listStr)
| tupleStr
| dictStr)
tupleStr << (lparen
+ pp.Optional(pp.delimitedList(listItem))
+ pp.Optional(comma)
+ rparen)
tupleStr.setParseAction(cvtTuple)
listStr << (lbrack
+ pp.Optional(pp.delimitedList(listItem) + pp.Optional(comma))
+ rbrack)
listStr.setParseAction(cvtList, lambda t: t[0])
dictEntry = pp.Group(listItem + colon + listItem)
dictStr << (lbrace
+ pp.Optional(pp.delimitedList(dictEntry) + pp.Optional(comma))
+ rbrace)
dictStr.setParseAction(cvtDict)
tests = """['a', 100, ('A', [101,102]), 3.14, [ +2.718, 'xyzzy', -1.414] ]
[{0: [2], 1: []}, {0: [], 1: [], 2: []}, {0: [1, 2]}]
{ 'A':1, 'B':2, 'C': {'a': 1.2, 'b': 3.4} }
3.14159
42
6.02E23
6.02e+023
1.0e-7
'a quoted string'"""
listItem.runTests(tests)
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