def visit_ProcedureDecl(self, node):
proc_name = node.proc_name
proc_symbol = ProcedureSymbol(proc_name)
self.current_scope.insert(proc_symbol)
result_str = "procedure %s%s" % (proc_name,
self.current_scope.scope_level)
procedure_scope = ScopedSymbolTable(
scope_name=proc_name,
scope_level=self.current_scope.scope_level + 1,
enclosing_scope=self.current_scope)
self.current_scope = procedure_scope
if node.params:
result_str += "("
formal_params = []
for param in node.params:
param_type = self.current_scope.lookup(param.type_node.value)
param_name = param.var_node.value
var_symbol = VarSymbol(param_name, param_type)
self.current_scope.insert(var_symbol)
proc_symbol.params.append(var_symbol)
scope_level = str(self.current_scope.scope_level)
formal_params.append("%s : %s0" %
(param_name + scope_level, param_type.name))
result_str += "; ".join(formal_params)
if node.params:
result_str += ")"
result_str += ";"
result_str += "\n"
result_str += self.visit(node.block_node)
result_str += "; {END OF %s}" % proc_name
result_str = "\n".join(" " + line
for line in result_str.splitlines())
self.current_scope = self.current_scope.enclosing_scope
return result_str
def visit_ProcedureDecl(self, node):
proc_name = node.proc_name
proc_symbol = ProcedureSymbol(proc_name)
self.current_scope.insert(proc_symbol)
print('ENTER scope: %s' % proc_name)
# Scope for parameters and local variables
procedure_scope = ScopedSymbolTable(
scope_name=proc_name,
scope_level=self.current_scope.scope_level + 1,
enclosing_scope=self.current_scope)
self.current_scope = procedure_scope
# Insert parameters into the procedure scope
for param in node.params:
param_type = self.current_scope.lookup(param.type_node.value)
param_name = param.var_node.value
var_symbol = VarSymbol(param_name, param_type)
self.current_scope.insert(var_symbol)
proc_symbol.params.append(var_symbol)
self.visit(node.block_node)
print(procedure_scope)
self.current_scope = self.current_scope.enclosing_scope
print('LEAVE scope: %s' % proc_name)
def visit_VarDecl(self, node):
type_name = node.type_node.value
type_symbol = self.symtab.lookup(type_name)
# We have all the information we need to create a variable symbol.
# Create the symbol and insert it into the symbol table.
var_name = node.var_node.value
var_symbol = VarSymbol(var_name, type_symbol)
self.symtab.insert(var_symbol)
def visit_VarDecl(self, node):
type_name = node.type_node.value
type_symbol = self.scope.lookup(type_name)
# Create the symbol and insert it into the symbol table.
var_name = node.var_node.value
var_symbol = VarSymbol(var_name, type_symbol)
self.scope.insert(var_symbol)
def visit_VarDecl(self, node):
# For now, manually create a symbol for the INTEGER built-in type
# and insert the type symbol in the symbol table.
type_symbol = BuiltinTypeSymbol('INTEGER')
self.symtab.insert(type_symbol)
# We have all the information we need to create a variable symbol.
# Create the symbol and insert it into the symbol table.
var_name = node.var_node.value
var_symbol = VarSymbol(var_name, type_symbol)
self.symtab.insert(var_symbol)
def visit_VarDecl(self, node):
type_name = node.type_node.value
type_symbol = self.current_scope.lookup(type_name)
var_name = node.var_node.value
var_symbol = VarSymbol(var_name, type_symbol)
if self.current_scope.lookup(var_name, current_scope_only=True):
raise Exception("Error: Duplicate identifier '%s' found" %
var_name)
self.current_scope.insert(var_symbol)
scope_level = str(self.current_scope.scope_level)
return " var %s : %s0;" % (var_name + scope_level, type_name)
def visit_VarDecl(self, node):
type_name = node.type_node.value
type_symbol = self.symtab.lookup(type_name)
# We have all the information we need to create a variable symbol.
# Create the symbol and insert it into the symbol table.
var_name = node.var_node.value
var_symbol = VarSymbol(var_name, type_symbol)
# Signal an error if the table alrady has a symbol
# with the same name
if self.symtab.lookup(var_name) is not None:
raise Exception("Error: Duplicate identifier '%s' found" %
var_name)
self.symtab.insert(var_symbol)
def visit_ProcedureDecl(self, node):
proc_name = node.proc_name
proc_symbol = ProcedureSymbol(proc_name)
self.current_scope.insert(proc_symbol)
result_str = 'procedure %s%s' % (proc_name,
self.current_scope.scope_level)
# Scope for parameters and local variables
procedure_scope = ScopedSymbolTable(
scope_name=proc_name,
scope_level=self.current_scope.scope_level + 1,
enclosing_scope=self.current_scope)
self.current_scope = procedure_scope
if node.params:
result_str += '('
formal_params = []
# Insert parameters into the procedure scope
for param in node.params:
param_type = self.current_scope.lookup(param.type_node.value)
param_name = param.var_node.value
var_symbol = VarSymbol(param_name, param_type)
self.current_scope.insert(var_symbol)
proc_symbol.params.append(var_symbol)
scope_level = str(self.current_scope.scope_level)
formal_params.append('%s : %s' %
(param_name + scope_level, param_type.name))
result_str += '; '.join(formal_params)
if node.params:
result_str += ')'
result_str += ';'
result_str += '\n'
result_str += self.visit(node.block_node)
result_str += '; {END OF %s}' % proc_name
# indent procedure text
result_str = '\n'.join(' ' + line
for line in result_str.splitlines())
self.current_scope = self.current_scope.enclosing_scope
return result_str
def visit_VarDecl(self, node):
type_name = node.type_node.value
type_symbol = self.current_scope.lookup(type_name)
# We have all the information we need to create a variable symbol.
# Create the symbol and insert it into the symbol table.
var_name = node.var_node.value
var_symbol = VarSymbol(var_name, type_symbol)
# Signal an error if the table alrady has a symbol
# with the same name
if self.current_scope.lookup(var_name, current_scope_only=True):
raise Exception("Error: Duplicate identifier '%s' found" %
var_name)
self.current_scope.insert(var_symbol)
scope_level = str(self.current_scope.scope_level)
return ' var %s : %s;' % (var_name + scope_level, type_name)
return s
__repr__ = __str__
def insert(self, symbol):
print('Insert: %s' % symbol.name)
self._symbols[symbol.name] = symbol
if __name__ == '__main__':
text = """
program SymTab1;
var x, y : integer;
begin
end.
"""
lexer = Lexer(text)
parser = Parser(lexer)
tree = parser.parse()
symtab = SymbolTable()
int_type = BuiltinTypeSymbol('INTEGER')
symtab.insert(int_type)
var_x_symbol = VarSymbol('x', int_type)
symtab.insert(var_x_symbol)
var_y_symbol = VarSymbol('y', int_type)
symtab.insert(var_y_symbol)
print(symtab)
