From 39656a3801bb311edd9ebb65e92a24fc48f69ec7 Mon Sep 17 00:00:00 2001 From: Griffin Smith Date: Sun, 14 Mar 2021 11:53:13 -0400 Subject: Add string support to the frontend --- src/parser/expr.rs | 34 ++++++++++++++++++++++++++++++---- 1 file changed, 30 insertions(+), 4 deletions(-) (limited to 'src/parser/expr.rs') diff --git a/src/parser/expr.rs b/src/parser/expr.rs index 73c873b5b3..2ec6d60cd0 100644 --- a/src/parser/expr.rs +++ b/src/parser/expr.rs @@ -1,11 +1,14 @@ +use std::borrow::Cow; + +use nom::alt; use nom::character::complete::{digit1, multispace0, multispace1}; use nom::{ - alt, call, char, complete, delimited, do_parse, flat_map, many0, map, named, opt, parse_to, + call, char, complete, delimited, do_parse, flat_map, many0, map, named, opt, parse_to, preceded, separated_list0, separated_list1, tag, tuple, }; use pratt::{Affix, Associativity, PrattParser, Precedence}; -use crate::ast::{BinaryOperator, Binding, Expr, Fun, Ident, Literal, UnaryOperator}; +use crate::ast::{BinaryOperator, Binding, Expr, Fun, Literal, UnaryOperator}; use crate::parser::{ident, type_}; #[derive(Debug)] @@ -161,7 +164,22 @@ named!(bool_(&str) -> Literal, alt!( tag!("false") => { |_| Literal::Bool(false) } )); -named!(literal(&str) -> Literal, alt!(int | bool_)); +fn string_internal(i: &str) -> nom::IResult<&str, Cow<'_, str>, nom::error::Error<&str>> { + let (s, rem) = i + .split_once('"') + .ok_or_else(|| nom::Err::Error(nom::error::Error::new(i, nom::error::ErrorKind::Tag)))?; + Ok((rem, Cow::Borrowed(s))) +} + +named!(string(&str) -> Literal, preceded!( + char!('"'), + map!( + string_internal, + |s| Literal::String(s) + ) +)); + +named!(literal(&str) -> Literal, alt!(int | bool_ | string)); named!(literal_expr(&str) -> Expr, map!(literal, Expr::Literal)); @@ -308,7 +326,7 @@ named!(pub expr(&str) -> Expr, alt!( #[cfg(test)] pub(crate) mod tests { use super::*; - use crate::ast::Type; + use crate::ast::{Ident, Type}; use std::convert::TryFrom; use BinaryOperator::*; use Expr::{BinaryOp, If, Let, UnaryOp}; @@ -418,6 +436,14 @@ pub(crate) mod tests { ); } + #[test] + fn simple_string_lit() { + assert_eq!( + test_parse!(expr, "\"foobar\""), + Expr::Literal(Literal::String(Cow::Borrowed("foobar"))) + ) + } + #[test] fn let_complex() { let res = test_parse!(expr, "let x = 1; y = x * 7 in (x + y) * 4"); -- cgit 1.4.1