def p_Number(self, token):
s = token.text
# sign
if s[0] == "-":
s = s[1:]
sign = -1
else:
sign = 1
# base
s = s.split("^^")
if len(s) == 1:
base, s = 10, s[0]
else:
assert len(s) == 2
base, s = int(s[0]), s[1]
if not 2 <= base <= 36:
self.tokeniser.feeder.message("General", "base", base,
token.text, 36)
self.tokeniser.sntx_message(token.pos)
raise InvalidSyntaxError()
# mantissa
s = s.split("*^")
if len(s) == 1:
exp, s = 0, s[0]
else:
# TODO modify regex and provide error if `exp` is not an int
exp, s = int(s[1]), s[0]
# precision/accuracy
s = s.split("`", 1)
if len(s) == 1:
s, suffix = s[0], None
else:
s, suffix = s[0], s[1]
for i, c in enumerate(s.lower()):
if permitted_digits[c] >= base:
self.tokeniser.feeder.message("General", "digit", i + 1, s,
base)
self.tokeniser.sntx_message(token.pos)
raise InvalidSyntaxError()
result = Number(s, sign=sign, base=base, suffix=suffix, exp=exp)
self.consume()
return result
def expect(self, expected_tag):
token = self.next_noend()
if token.tag == expected_tag:
self.consume()
else:
self.tokeniser.sntx_message(token.pos)
raise InvalidSyntaxError()
def p_Information(self, token):
self.consume()
q = prefix_ops["Information"]
child = self.parse_exp(q)
if child.__class__ is not Symbol:
raise InvalidSyntaxError()
return Node("Information", child,
Node("Rule", Symbol("LongForm"), Symbol("True")))
def parse_p(self):
token = self.next_noend()
tag = token.tag
method = getattr(self, "p_" + tag, None)
if method is not None:
return method(token)
elif tag in prefix_ops:
self.consume()
q = prefix_ops[tag]
child = self.parse_exp(q)
return Node(tag, child)
else:
self.tokeniser.sntx_message(token.pos)
raise InvalidSyntaxError()
def e_MessageName(self, expr1, token, p):
leaves = [expr1]
while self.next().tag == "MessageName":
self.consume()
token = self.next()
if token.tag == "Symbol":
# silently convert Symbol to String
self.consume()
leaf = String(token.text)
elif token.tag == "String":
leaf = self.p_String(token)
else:
self.tokeniser.sntx_message(token.pos)
raise InvalidSyntaxError()
leaves.append(leaf)
return Node("MessageName", *leaves)
def parse_binary(self, expr1, token, p):
tag = token.tag
q = binary_ops[tag]
if q < p:
return None
self.consume()
if tag not in right_binary_ops:
q += 1
expr2 = self.parse_exp(q)
# flatten or associate
if (tag in nonassoc_binary_ops and expr1.get_head_name() == tag
and not expr1.parenthesised):
self.tokeniser.sntx_message(token.pos)
raise InvalidSyntaxError()
result = Node(tag, expr1, expr2)
if tag in flat_binary_ops:
result.flatten()
return result
def e_TagSet(self, expr1, token, p):
q = all_ops["Set"]
if q < p:
return None
self.consume()
expr2 = self.parse_exp(q + 1)
# examine next token
token = self.next_noend()
tag = token.tag
if tag == "Set":
head = "TagSet"
elif tag == "SetDelayed":
head = "TagSetDelayed"
elif tag == "Unset":
head = "TagUnset"
else:
self.tokeniser.sntx_message(token.pos)
raise InvalidSyntaxError()
self.consume()
if head == "TagUnset":
return Node(head, expr1, expr2)
expr3 = self.parse_exp(q + 1)
return Node(head, expr1, expr2, expr3)