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"""trivialjson (https://github.com/phihag/trivialjson)"""
import re
def loads(s):
s = s.decode('UTF-8')
def raiseError(msg, i):
raise ValueError(msg + ' at position ' + str(i) + ' of ' + repr(s) + ': ' + repr(s[i:]))
def skipSpace(i, expectMore=True):
while i < len(s) and s[i] in ' \t\r\n':
i += 1
if expectMore:
if i >= len(s):
raiseError('Premature end', i)
return i
def decodeEscape(match):
esc = match.group(1)
_STATIC = {
'"': '"',
'\\': '\\',
'/': '/',
'b': unichr(0x8),
'f': unichr(0xc),
'n': '\n',
'r': '\r',
't': '\t',
}
if esc in _STATIC:
return _STATIC[esc]
if esc[0] == 'u':
if len(esc) == 1+4:
return unichr(int(esc[1:5], 16))
if len(esc) == 5+6 and esc[5:7] == '\\u':
hi = int(esc[1:5], 16)
low = int(esc[7:11], 16)
return unichr((hi - 0xd800) * 0x400 + low - 0xdc00 + 0x10000)
raise ValueError('Unknown escape ' + str(esc))
def parseString(i):
i += 1
e = i
while True:
e = s.index('"', e)
bslashes = 0
while s[e-bslashes-1] == '\\':
bslashes += 1
if bslashes % 2 == 1:
e += 1
continue
break
rexp = re.compile(r'\\(u[dD][89aAbB][0-9a-fA-F]{2}\\u[0-9a-fA-F]{4}|u[0-9a-fA-F]{4}|.|$)')
stri = rexp.sub(decodeEscape, s[i:e])
return (e+1,stri)
def parseObj(i):
i += 1
res = {}
i = skipSpace(i)
if s[i] == '}': # Empty dictionary
return (i+1,res)
while True:
if s[i] != '"':
raiseError('Expected a string object key', i)
i,key = parseString(i)
i = skipSpace(i)
if i >= len(s) or s[i] != ':':
raiseError('Expected a colon', i)
i,val = parse(i+1)
res[key] = val
i = skipSpace(i)
if s[i] == '}':
return (i+1, res)
if s[i] != ',':
raiseError('Expected comma or closing curly brace', i)
i = skipSpace(i+1)
def parseArray(i):
res = []
i = skipSpace(i+1)
if s[i] == ']': # Empty array
return (i+1,res)
while True:
i,val = parse(i)
res.append(val)
i = skipSpace(i) # Raise exception if premature end
if s[i] == ']':
return (i+1, res)
if s[i] != ',':
raiseError('Expected a comma or closing bracket', i)
i = skipSpace(i+1)
def parseDiscrete(i):
for k,v in {'true': True, 'false': False, 'null': None}.items():
if s.startswith(k, i):
return (i+len(k), v)
raiseError('Not a boolean (or null)', i)
def parseNumber(i):
mobj = re.match('^(-?(0|[1-9][0-9]*)(\.[0-9]*)?([eE][+-]?[0-9]+)?)', s[i:])
if mobj is None:
raiseError('Not a number', i)
nums = mobj.group(1)
if '.' in nums or 'e' in nums or 'E' in nums:
return (i+len(nums), float(nums))
return (i+len(nums), int(nums))
CHARMAP = {'{': parseObj, '[': parseArray, '"': parseString, 't': parseDiscrete, 'f': parseDiscrete, 'n': parseDiscrete}
def parse(i):
i = skipSpace(i)
i,res = CHARMAP.get(s[i], parseNumber)(i)
i = skipSpace(i, False)
return (i,res)
i,res = parse(0)
if i < len(s):
raise ValueError('Extra data at end of input (index ' + str(i) + ' of ' + repr(s) + ': ' + repr(s[i:]) + ')')
return res
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