# parsePythonValue.py
#
# Copyright, 2006, by Paul McGuire
#
from pyparsing import *
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())
# define punctuation as suppressed literals
lparen,rparen,lbrack,rbrack,lbrace,rbrace,colon = \
map(Suppress,"()[]{}:")
integer = Combine(Optional(oneOf("+ -")) + Word(nums))\
.setName("integer")\
.setParseAction( cvtInt )
real = Combine(Optional(oneOf("+ -")) + Word(nums) + "." +
Optional(Word(nums)) +
Optional(oneOf("e E")+Optional(oneOf("+ -")) +Word(nums)))\
.setName("real")\
.setParseAction( cvtReal )
tupleStr = Forward()
listStr = Forward()
dictStr = Forward()
unicodeString.setParseAction(lambda t:t[0][2:-1].decode('unicode-escape'))
quotedString.setParseAction(lambda t:t[0][1:-1].decode('string-escape'))
boolLiteral = oneOf("True False").setParseAction(cvtBool)
noneLiteral = Literal("None").setParseAction(replaceWith(None))
listItem = real|integer|quotedString|unicodeString|boolLiteral|noneLiteral| \
Group(listStr) | tupleStr | dictStr
tupleStr << ( Suppress("(") + Optional(delimitedList(listItem)) +
Optional(Suppress(",")) + Suppress(")") )
tupleStr.setParseAction( cvtTuple )
listStr << (lbrack + Optional(delimitedList(listItem) +
Optional(Suppress(","))) + rbrack)
dictEntry = Group( listItem + colon + listItem )
dictStr << (lbrace + Optional(delimitedList(dictEntry) + \
Optional(Suppress(","))) + 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'""".split("\n")
for test in tests:
print "Test:", test.strip()
result = listItem.parseString(test)[0]
print "Result:", result
try:
for dd in result:
if isinstance(dd,dict): print dd.items()
except TypeError,te:
pass
print
|