def add(self, identifier, is_global=False):
"""
Add Identifier to Scope. Adds a new identifier to
either the current scope of global.
Arguments:
identifier: An Identifier named tuple object describing the new
identifier to add to the table.
is_global: Determines whether the identifier should be added to
the current scope or the global scope. (Default: False)
Raises:
ParserNameError if the identifier has been declared at this scope.
"""
scope = -1 if not is_global else 0
if is_global and len(self) > 2:
raise ParserNameError(f'Global name "{identifier.name}" must be defined in program scope')
if is_global and (identifier.name in self[0] or (len(self) > 1 and
identifier.name in self[1])):
raise ParserNameError(f'Name "{identifier.name}" already declared at this scope')
if not is_global and identifier.name in self[-1]:
raise ParserNameError(f'Name "{identifier.name}" already declared at this scope')
self[scope][identifier.name] = identifier
def find(self, name):
"""Find Identifier in Scope
Searches for the given identifier in the current and global scope.
Arguments:
name: The identifier name for which to search.
Returns:
An Identifier named tuple containing identifier name, type and size
information if found in the current or global scopes.
Raises:
ParserNameError if the given identifier is not found in any valid scope.
"""
identifier = None
if name in self[-1]:
identifier = self[-1][name]
elif name in self[0]:
identifier = self[0][name]
else:
raise ParserNameError()
return identifier
def add(self, identifier, is_global=False):
scope = -1 if not is_global else 0
if is_global and len(self) > 2:
raise ParserNameError(
'global name must be defined in program scope')
if is_global and (identifier.name in self[0] or
(len(self) > 1 and identifier.name in self[1])):
raise ParserNameError('name already declared at this scope')
if not is_global and identifier.name in self[-1]:
raise ParserNameError('name already declared at this scope')
self[scope][identifier.name] = identifier
return
def find(self, name):
if name in self[-1]:
identifier = self[-1][name]
elif name in self[0]:
identifier = self[0][name]
else:
raise ParserNameError()
return identifier