def p_while(p):
'''while : WHILE expression DO block'''
p[0] = ast.WhileNode(expression=p[2], block=p[4])
def p_stmt_while(p):
"""stmt : WHILE LROUND condn RROUND LCURLY stmt_list RCURLY"""
p[0] = ast.WhileNode(p[3], p[6])
def p_Whileblock(p):
'statement : WHILE LPAREN expression RPAREN block'
# print("in while grammar")
p[0] = tree.WhileNode(p[3], p[5])
def parse_statement(self):
token = self.get_current_token()
if token.is_type():
lookup2 = self.lookup_for_n(2)
if lookup2.word == ';':
return self.parse_var_decl()
elif lookup2.word == '=':
return self.parse_var_decl_and_assign()
elif lookup2.word == '[':
lookup5 = self.lookup_for_n(5)
if lookup5.word == '=':
return self.parse_array_decl_and_assign()
elif lookup5.word == ';':
return self.parse_array_decl()
else:
raise cmexception.SyntaxException(lookup5, ['=', ';'])
else:
raise cmexception.SyntaxException(lookup2, [';', '=', '['])
elif token.lexme_type == LexmeType.Variable:
lookup1 = self.lookup_for_n(1)
if lookup1.word == '[':
return self.parse_array_assign()
elif lookup1.word == '=':
return self.parse_var_assign()
elif lookup1.word == '(':
node = self.parse_function_call()
self.move_for_n(1)
return node
else:
raise cmexception.SyntaxException(lookup1, ['=', '['])
elif token.word == '{':
self.move_for_n(1)
nodes = self.parse_stmtlist()
right_bracket = self.get_current_token()
if right_bracket.word == '}':
self.move_for_n(1)
return nodes
else:
raise cmexception.SyntaxException(right_bracket, ['}'])
elif token.word == 'if':
left_brace = self.move_for_n(1)
if left_brace.word == '(':
self.move_for_n(1)
condition_expr = self.parse_expr()
right_brace = self.get_current_token()
if right_brace.word == ')':
self.move_for_n(1)
if_node = ast.IfNode(self.context, self.parse_statement())
else_node = self.parse_else_statement()
return ast.IfElseNode(self.context, condition_expr,
if_node, else_node)
else:
raise cmexception.SyntaxException(right_brace, [')'])
else:
raise cmexception.SyntaxException(left_brace, ['('])
elif token.word == 'while':
left_brace = self.lookup_for_n(1)
if left_brace.word == '(':
self.move_for_n(2)
expr_node = self.parse_expr()
right_brace = self.get_current_token()
if right_brace.word == ')':
self.move_for_n(1)
stmtnode = self.parse_statement()
return ast.WhileNode(self.context, expr_node, stmtnode)
else:
raise cmexception.SyntaxException(right_brace, [')'])
else:
raise cmexception.SyntaxException(left_brace, ['('])
elif token.word == 'return':
s = self.move_for_n(1)
if s.word == ';':
self.move_for_n(1)
return ast.ReturnNode(self.context, token, None)
else:
node = self.parse_expr_or_string()
if self.get_current_token().word == ';':
self.move_for_n(1)
return ast.ReturnNode(self.context, token, node)
else:
return cmexception.SyntaxException(
self.get_current_token(), [';'])
else:
raise cmexception.SyntaxException(
token,
['<legal identifier>', 'while', 'return', 'if', '<type>'])
def p_structure(p):
''' structure : WHILE expression "{" program "}" '''
p[0] = ast.WhileNode([p[2], p[4]])