def _for_statement(self) -> st.While:
self._consume(TokenType.LEFT_PAREN, "Expect '(' after 'for'.")
initializer = None
if self._match(TokenType.SEMICOLON):
pass
elif self._match(TokenType.VAR):
initializer = self._variable_declaration()
else:
initializer = self._expression_statement()
condition = ex.Literal(True) if self._check(
TokenType.SEMICOLON) else self._expression()
self._consume(TokenType.SEMICOLON, "Expect ';' after loop condition.")
increment = None if self._check(
TokenType.RIGHT_PAREN) else self._expression()
self._consume(TokenType.RIGHT_PAREN, "Expect ')' after for clauses.")
body = self._statement()
if increment is not None:
body = st.Block([body, st.Expression(increment)])
body = st.While(condition, body)
if initializer is not None:
body = st.Block([initializer, body])
return body
def for_statement(self):
self.consume(TokenType.LEFT_PAREN, "Expect '(' after 'for'.")
if self.match(TokenType.SEMICOLON):
initializer = None
elif self.match(TokenType.VAR):
initializer = self.var_declaration()
else:
initializer = self.expression_statement()
condition = None
if not self.check(TokenType.SEMICOLON):
condition = self.expression()
self.consume(TokenType.SEMICOLON, "Expect ';' after loop condition.")
increment = None
if not self.check(TokenType.RIGHT_PAREN):
increment = self.expression()
self.consume(TokenType.RIGHT_PAREN, "Expect ')' after for clauses.")
body = self.statement()
if increment is not None:
body = Stmt.Block(list(body), Stmt.Expression(increment))
if condition is None:
condition = Expr.Literal(True)
body = Stmt.While(condition, body)
if initializer is not None:
body = Stmt.Block(list(initializer), body)
return body
def forStatement(self) -> s.Stmt:
self.consume(TokenType.LEFT_PAREN, "Expect '(' after 'for'.")
if self.match(TokenType.SEMICOLON):
initializer = None
elif self.match(TokenType.VAR):
initializer = self.varDeclaration()
else:
initializer = self.expressionStatement()
condition = None
if not self.check(TokenType.SEMICOLON):
condition = self.expression()
self.consume(TokenType.SEMICOLON, "Expect ';' after loop condition.")
increment = None
if not self.check(TokenType.RIGHT_PAREN):
increment = self.expression()
self.consume(TokenType.RIGHT_PAREN, "Expect ')' after for clauses.")
body: s.Stmt = self.statement()
# not null
if increment:
body = s.Block([body, s.Expression(increment)])
# is null
if condition is None:
condition = e.Literal(True)
body = s.While(condition, body)
# not null
if initializer:
body = s.Block([initializer, body])
return body
def _expression_statement(self) -> st.Expression:
value = self._expression()
self._consume(TokenType.SEMICOLON, "Expect a ';' after expression.")
return st.Expression(value)
def expressionStatement(self) -> s.Stmt:
expr: e.Expr = self.expression()
self.consume(TokenType.SEMICOLON, "Expect ';' after expression.")
return s.Expression(expr)
def expressionStatement(self):
value = self.expression()
return Stmt.Expression(value)
def expression_statement(self):
expr = self.expression()
if not self.is_at_end():
self.consume(TT.NEWLINE, "Expect newline after expression.")
return stmt.Expression(expr)
def expression_statement(self):
expr = self.expression()
self.consume(TokenType.SEMICOLON, "Expect ';' after expression.")
return Stmt.Expression(expr)