def __getattr__(self, attr: str) -> TokenAction:
"""
Shortcut to get a TokenAction stored in self.tokens.
"""
name = Name.from_camel(attr)
try:
return self.tokens.name_to_token[name]
except KeyError:
raise AttributeError(f"No such token: {attr}")
def __new__(mcs, name, bases, dct):
assert len(bases) == 1, (
"Multiple inheritance for LexerToken subclasses is not supported"
)
fields = []
for fld_name, fld_value in dct.items():
if isinstance(fld_value, TokenAction):
fld_value.name = Name.from_camel(fld_name)
fields.append(fld_value)
dct['fields'] = getattr(bases[0], 'fields', []) + fields
return type.__new__(mcs, name, bases, dct)
def add_tokens(self, cls):
for fld_name, fld_value in cls.__dict__.items():
if isinstance(fld_value, TokenAction):
dest_list = self.tokens
elif isinstance(fld_value, TokenFamily):
dest_list = self.token_families
else:
continue
# Several items here are shared: for example, the
# LexerToken.LexingFailure instance can be used in two different
# lexers, so we can't assume its name is always None. Just accept
# when it has already the expected name.
name = Name.from_camel(fld_name)
assert fld_value.name in (None, name)
fld_value.name = name
dest_list.append(fld_value)
def add_tokens(self, klass):
for fld_name, fld_value in klass.__dict__.items():
if isinstance(fld_value, TokenAction):
fld_value.name = Name.from_camel(fld_name)
self.fields.append(fld_value)
