From 7140082ff641732ba9323086cf0758fe23ef262f Mon Sep 17 00:00:00 2001 From: Erin Date: Mon, 6 Jun 2022 23:30:08 +0200 Subject: [PATCH] Parser cleanup --- ablescript/src/parser.rs | 112 +++++++++++---------------------------- 1 file changed, 30 insertions(+), 82 deletions(-) diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs index def257b..4967275 100644 --- a/ablescript/src/parser.rs +++ b/ablescript/src/parser.rs @@ -66,39 +66,15 @@ impl<'source> Parser<'source> { let start = self.lexer.span().start; match token { - Token::Unless => Ok(Spanned::new( - self.unless_flow()?, - start..self.lexer.span().end, - )), - Token::Functio => Ok(Spanned::new( - self.functio_flow()?, - start..self.lexer.span().end, - )), - Token::Bff => Ok(Spanned::new(self.bff_flow()?, start..self.lexer.span().end)), - Token::Melo => Ok(Spanned::new( - self.melo_flow()?, - start..self.lexer.span().end, - )), - Token::Loop => Ok(Spanned::new( - self.loop_flow()?, - start..self.lexer.span().end, - )), - Token::Enough => Ok(Spanned::new( - self.semicolon_terminated(Stmt::Enough)?, - start..self.lexer.span().end, - )), - Token::AndAgain => Ok(Spanned::new( - self.semicolon_terminated(Stmt::AndAgain)?, - start..self.lexer.span().end, - )), - Token::Rlyeh => Ok(Spanned::new( - self.semicolon_terminated(Stmt::Rlyeh)?, - start..self.lexer.span().end, - )), - Token::Rickroll => Ok(Spanned::new( - self.semicolon_terminated(Stmt::Rickroll)?, - start..self.lexer.span().end, - )), + Token::Unless => self.unless_flow(), + Token::Functio => self.functio_flow(), + Token::Bff => self.bff_flow(), + Token::Melo => self.melo_flow(), + Token::Loop => self.loop_flow(), + Token::Enough => self.semicolon_terminated(Stmt::Enough), + Token::AndAgain => self.semicolon_terminated(Stmt::AndAgain), + Token::Rlyeh => self.semicolon_terminated(Stmt::Rlyeh), + Token::Rickroll => self.semicolon_terminated(Stmt::Rickroll), Token::Identifier(_) | Token::String(_) @@ -106,16 +82,14 @@ impl<'source> Parser<'source> { | Token::Char(_) | Token::Aint | Token::LeftBracket - | Token::LeftParen => Ok(Spanned::new( - self.value_flow(token)?, - start..self.lexer.span().end, - )), + | Token::LeftParen => self.value_flow(token), t => Err(Error { kind: ErrorKind::UnexpectedToken(t), span: start..self.lexer.span().end, }), } + .map(|stmt| Spanned::new(stmt, start..self.lexer.span().end)) } /// Require statement to be semicolon terminated @@ -161,43 +135,21 @@ impl<'source> Parser<'source> { match token { // Values - Token::Identifier(i) => Ok(Spanned::new( - Expr::Variable(self.tdark_subst(i)), - start..self.lexer.span().end, - )), - Token::Integer(i) => Ok(Spanned::new( - Expr::Literal(Literal::Int(i)), - start..self.lexer.span().end, - )), - Token::String(s) => Ok(Spanned::new( - Expr::Literal(Literal::Str(self.tdark_subst(s))), - start..self.lexer.span().end, - )), - Token::Char(c) => Ok(Spanned::new( - Expr::Literal(Literal::Char(c)), - start..self.lexer.span().end, - )), - + Token::Identifier(i) => Ok(Expr::Variable(self.tdark_subst(i))), + Token::Integer(i) => Ok(Expr::Literal(Literal::Int(i))), + Token::String(s) => Ok(Expr::Literal(Literal::Str(self.tdark_subst(s)))), + Token::Char(c) => Ok(Expr::Literal(Literal::Char(c))), Token::LeftBracket => match buf.take() { - Some(buf) => Ok(Spanned::new( - self.index_flow(buf)?, - start..self.lexer.span().end, - )), - None => Ok(Spanned::new( - self.cart_flow()?, - start..self.lexer.span().end, - )), + Some(buf) => self.index_flow(buf), + None => self.cart_flow(), }, // Operations - Token::Aint if buf.is_none() => Ok(Spanned::new( - { - let next = self.checked_next()?; - Expr::Aint(Box::new(self.parse_expr(next, buf)?)) - }, - start..self.lexer.span().end, - )), - + Token::Aint if buf.is_none() => { + let next = self.checked_next()?; + Ok(Expr::Aint(Box::new(self.parse_expr(next, buf)?))) + } + Token::Plus | Token::Minus | Token::Star @@ -205,17 +157,15 @@ impl<'source> Parser<'source> { | Token::Equals | Token::LessThan | Token::GreaterThan - | Token::Aint => Ok(Spanned::new( - self.binop_flow( - BinOpKind::from_token(token).map_err(|e| Error::new(e, self.lexer.span()))?, - buf, - )?, - start..self.lexer.span().end, - )), + | Token::Aint => self.binop_flow( + BinOpKind::from_token(token).map_err(|e| Error::new(e, self.lexer.span()))?, + buf, + ), - Token::LeftParen => self.expr_flow(Token::RightParen), + Token::LeftParen => return self.expr_flow(Token::RightParen), t => Err(Error::new(ErrorKind::UnexpectedToken(t), self.lexer.span())), } + .map(|expr| Spanned::new(expr, start..self.lexer.span().end)) } /// Flow for creating carts @@ -358,7 +308,7 @@ impl<'source> Parser<'source> { /// will parse it to function call or print statement. fn value_flow(&mut self, init: Token) -> Result { let mut buf = Some(self.parse_expr(init, &mut None)?); - let r = loop { + Ok(loop { match self.checked_next()? { // Print to stdout Token::Print => { @@ -443,9 +393,7 @@ impl<'source> Parser<'source> { t => buf = Some(self.parse_expr(t, &mut buf)?), } - }; - - Ok(r) + }) } /// Parse Unless flow