def parse_declaration(self):
token = self.token_current()
if (token.type == scanner.TK_VAR):
self.token_accept(scanner.TK_VAR)
token = self.token_current()
if (token.type == scanner.TK_IDENTIFIER):
self.token_accept(scanner.TK_IDENTIFIER)
self.token_accept(scanner.TK_COLON)
e1 = self.parse_type_denoter()
return ast.VarDeclaration(token.val, e1)
else:
raise ParserError(self.curtoken.pos, self.curtoken.type)
if (token.type == scanner.TK_CONST):
self.token_accept_any()
token = self.token_current()
if (token.type == scanner.TK_IDENTIFIER):
self.token_accept_any()
self.token_accept(scanner.TK_IS)
e1 = self.parse_expr()
return ast.ConstDeclaration(token.val, e1)
else:
raise ParserError(self.curtoken.pos, self.curtoken.type)
else: #just added
raise ParserError(self.curtoken.pos, self.curtoken.type)
def parse_single_declaration(self):
"""const Identifier ~ Expression ';'
| var Identifier : Type-denoter ';'
| func Identifier '(' parameter-list ')' ':'' Type-denoter single-Command
"""
# Constant Declaration
if self.curtoken.type == scanner.TK_CONST:
self.token_accept_any()
name = self.token_current().val
self.token_accept(scanner.TK_IDENTIFIER)
self.token_accept(scanner.TK_IS)
expr = self.parse_expression()
self.token_accept(scanner.TK_SEMICOLON)
return ast.ConstDeclaration(name, expr)
# Variable Declaration
elif self.curtoken.type == scanner.TK_VAR:
self.token_accept_any()
name = self.token_current().val
self.token_accept(scanner.TK_IDENTIFIER)
self.token_accept(scanner.TK_COLON)
type_d = ast.TypeDenoter(self.token_current().val)
self.token_accept(scanner.TK_IDENTIFIER)
self.token_accept(scanner.TK_SEMICOLON)
return ast.VarDeclaration(name, type_d)
# Function Declaration
elif self.curtoken.type == scanner.TK_FUNCDEF:
return self.parse_function_declaration()
# Unexpected tokens
else:
raise ParserException(self.curtoken.pos, self.curtoken.type)
def parse_const_declaration(self):
self.token_accept_any()
token = self.token_current()
if (token.type == scanner.TK_IDENTIFIER):
self.token_accept_any()
self.token_accept(scanner.TK_IS)
e1 = self.parse_expr()
return ast.ConstDeclaration(token.val, e1)
else:
raise ParserError(self.curtoken.pos, self.curtoken.type)
def parse_single_declaration(self):
""" single-Declaration ::= const Identifier ~ Expression
| var Identifier : Type-denoter
| func Identifier '(' Identifier ':' Type-denoter ',*)' ':' Type-denoter single-Command
"""
token = self.token_current()
if token.type == scanner.TK_CONST:
self.token_accept_any()
token = self.token_current()
self.token_accept(scanner.TK_IDENTIFIER)
ident = token.val
self.token_accept(scanner.TK_IS)
expr = self.parse_expression()
decl = ast.ConstDeclaration(ident, expr)
elif token.type == scanner.TK_VAR:
self.token_accept_any()
token = self.token_current()
self.token_accept(scanner.TK_IDENTIFIER)
ident = token.val
self.token_accept(scanner.TK_COLON)
type_denoter = self.parse_type_denoter()
decl = ast.VarDeclaration(ident, type_denoter)
elif token.type == scanner.TK_FUNCDEF:
self.token_accept_any()
tk_ident = self.token_current()
self.token_accept(scanner.TK_IDENTIFIER)
self.token_accept(scanner.TK_LPAREN)
if self.token_current != scanner.TK_RPAREN:
argrs = self.parse_argr()
else:
argrs = ''
self.token_accept(scanner.TK_RPAREN)
self.token_accept(scanner.TK_COLON)
func_type = self.parse_type_denoter()
command = self.parse_single_command()
#decl = ast.FunctionDeclaration(tk_ident.val, tk_argident.val, arg_type, func_type, command)
decl = ast.FunctionDeclaration(tk_ident.val, argrs, func_type,
command)
else:
raise ParserError(self.curtoken.pos, self.curtoken.type)
return decl
def parse_secdeclaration(self):
"""
sec-Declaration ::= const Identifier ~ Expression
| var Identifier : Identifier
"""
token = self.token_current()
if token.type == scanner.TK_CONST:
self.token_accept_any()
ident = self.token_current().val
self.token_accept(scanner.TK_IDENTIFIER)
self.token_accept(scanner.TK_IS)
expr = self.parse_expr()
return ast.ConstDeclaration(ident, expr)
elif token.type == scanner.TK_VAR:
self.token_accept_any()
ident = self.token_current().val
self.token_accept(scanner.TK_IDENTIFIER)
self.token_accept(scanner.TK_COLON)
type_denoter = self.parse_typedenoter()
return ast.VarDeclaration(ident, type_denoter)
else:
raise ParserError(self.curtoken.pos, self.curtoken.val,
self.curtoken.type)