def eval_var_node(node, semdata):
if node.scope not in semdata.symtbl:
create_scope(semdata, node.scope)
if not hasattr(node.child_value, "value"):
if all(param in semdata.symtbl[node.scope]["value"] for param in node.child_value.params):
eval_var_value(node, semdata)
else:
semdata.symtbl[node.scope]["no_value"].add(node)
else:
semdata.symtbl[node.scope]["value"][node.child_identifier.nodetype] = node.child_value.value
def eval_node(node, semdata):
symtbl = semdata.symtbl
nodetype = node.nodetype
s = 0
if nodetype == 'program':
# Copy and store current stack
semdata.old_stacks.append(semdata.stack.copy())
for i in node.children_definitions:
eval_node(i, semdata)
eval_node(node.child_returns, semdata)
# Restore stack
semdata.stack = semdata.old_stacks.pop()
return None
elif nodetype == "variable" or nodetype == "constant" or nodetype == "tuple":
eval_var_node(node, semdata)
elif nodetype == "function":
if "functions" not in symtbl:
symtbl["functions"] = {}
if node.child_identifier.nodetype not in semdata.symtbl:
create_scope(semdata, node.child_identifier.nodetype)
symtbl["functions"][node.child_identifier.nodetype] = {"defs" : node.children_definitions,
"return" : node.child_return,
"args" : node.args, }
for i in node.children_definitions:
eval_node(i, semdata)
elif nodetype == 'return_value':
if not hasattr(node, "value"):
if any(key not in symtbl[node.scope]["value"] for key in node.params) and hasattr(node, "args"):
eval_func(node, semdata)
elif all(key in symtbl[node.scope]["value"] for key in node.params):
re_eval_vars(semdata)
kwargs = {key: semdata.symtbl[node.scope]["value"].get(key) for key in node.params}
node.value = node.eval(**kwargs)
print("Return value of the program:", node.value)
def check_everything(node, semdata):
nodetype = node.nodetype
if hasattr(node, "error"):
return node.error
if nodetype == "variable":
if node.scope not in semdata.symtbl:
create_scope(semdata, node.scope)
semdata.symtbl[node.scope]["declared"] = set()
semdata.symtbl[node.scope]["declared"].add(
node.child_identifier.nodetype)
if node.child_value.nodetype == "evaluable":
for var in node.child_value.params:
if var not in semdata.symtbl[
node.scope]["declared"] and var not in semdata.symtbl[
"global"]["declared"]:
return "Referencing '" + var + "' that was not declared"
if nodetype == "constant" or nodetype == "tuple":
if node.scope not in semdata.symtbl:
create_scope(semdata, node.scope)
semdata.symtbl[node.scope]["declared"] = set()
if node.child_identifier.nodetype in semdata.symtbl[
node.scope]["declared"]:
return node.child_identifier.nodetype + "' cannot be defined again"
semdata.symtbl[node.scope]["declared"].add(
node.child_identifier.nodetype)
if node.child_value.nodetype == "evaluable":
for var in node.child_value.params:
if var not in semdata.symtbl[
node.scope]["declared"] and var not in semdata.symtbl[
"global"]["declared"]:
return "Referencing '" + var + "' that was not declared"
if nodetype == "function":
if node.child_return.scope not in semdata.symtbl:
create_scope(semdata, node.child_return.scope)
semdata.symtbl[node.child_identifier.nodetype]["declared"] = set()
semdata.symtbl["global"]["functions"][
node.child_identifier.nodetype] = len(node.args)
if node.child_identifier.nodetype in semdata.symtbl[
node.scope]["declared"]:
return "Function '" + node.child_identifier.nodetype + "' is already declared"
semdata.symtbl[node.scope]["declared"].add(
node.child_identifier.nodetype)
[
semdata.symtbl[node.child_identifier.nodetype]["declared"].add(
ident) for ident in node.args
]
if nodetype == "return_value":
if not hasattr(node, "value"):
for param in node.params:
if param not in semdata.symtbl[node.scope][
"declared"] and param not in semdata.symtbl["global"][
"declared"]:
return "Referencing '" + param + "' that was not declared"
if nodetype != "function" and hasattr(node, "args"):
func_found = False
for param in node.params:
if param in semdata.symtbl["global"]["functions"]:
func_found = True
if len(node.args
) != semdata.symtbl["global"]["functions"][param]:
return "Number of parameters do not match when calling '" + param + "'"
if not func_found:
return "Calling unknown function"
import tree_generation
import tree_print
parser = tree_generation.parser
if __name__ == "__main__":
import argparse, codecs
arg_parser = argparse.ArgumentParser()
arg_parser.add_argument('-f', '--file', help='filename to process')
ns = arg_parser.parse_args()
if ns.file is None:
arg_parser.print_help()
else:
data = codecs.open(ns.file, encoding='utf-8').read()
ast_tree = parser.parse(data, lexer=tokenizer.lexer, debug=False)
ast_tree.children_definitions.reverse()
tree_print.treeprint(ast_tree)
semdata = SemData()
semdata.in_function = None
semdata.symtbl = {}
create_scope(semdata, "global")
semdata.symtbl["global"]["declared"] = set()
semdata.symtbl["global"]["functions"] = dict()
semantic_checks(ast_tree, semdata)
print("Semantics ok:")