diff options
Diffstat (limited to 'src/lexer.rs')
| -rw-r--r-- | src/lexer.rs | 54 |
1 files changed, 28 insertions, 26 deletions
diff --git a/src/lexer.rs b/src/lexer.rs index 8617f4b..0b58293 100644 --- a/src/lexer.rs +++ b/src/lexer.rs @@ -64,7 +64,10 @@ pub enum Tok<'i> { } #[derive(Debug)] -pub struct LexicalError<'a>(pub usize, pub nom::Err<&'a str>); +pub enum LexicalError { + Error(usize, nom::simple_errors::Err<u32>), + Incomplete(nom::Needed), +} pub type Spanned<Tok, Loc, Error> = Result<(Loc, Tok, Loc), Error>; @@ -106,11 +109,11 @@ named!(identifier<&str, &str>, recognize!(preceded!( macro_rules! ident_tag { ($i:expr, $tag:expr) => { match identifier($i) { - Ok((i, s)) => { + nom::IResult::Done(i, s) => { if s == $tag { - Ok((i, s)) + nom::IResult::Done(i, s) } else { - Err(nom::Err::Error(error_position!($i, nom::ErrorKind::Tag))) + nom::IResult::Error(error_position!(nom::ErrorKind::Tag, $i)) } } r => r, @@ -143,20 +146,20 @@ named!(string_escape_numeric<&str, char>, map_opt!(alt!( ), ::std::char::from_u32)); fn string_lit_inner(input: &str) -> nom::IResult<&str, String> { - use nom::Err; + use nom::IResult::*;; use nom::ErrorKind; let mut s = String::new(); let mut cs = input.char_indices().peekable(); while let Some((i, c)) = cs.next() { match c { - '"' => return Ok((&input[i..], s)), + '"' => return nom::IResult::Done(&input[i..], s), '\\' => match cs.next() { Some((_, s)) if s.is_whitespace() => { while cs.peek().map(|&(_, s)| s.is_whitespace()) == Some(true) { let _ = cs.next(); } if cs.next().map(|p| p.1) != Some('\\') { - return Err(Err::Error(error_position!(input, ErrorKind::Custom(4 /* FIXME */)))); + return Error(error_position!(ErrorKind::Custom(4 /* FIXME */), input)); } } Some((j, ec)) => { @@ -165,23 +168,24 @@ fn string_lit_inner(input: &str) -> nom::IResult<&str, String> { // FIXME Named ASCII escapes and control character escapes } else { match string_escape_numeric(&input[j..]) { - Ok((rest, esc)) => { + Done(rest, esc) => { let &(k, _) = cs.peek().unwrap(); // digits are always single byte ASCII characters let consumed = input[k..].len() - rest.len(); for _ in 0..consumed { let _ = cs.next(); } s.push(esc); } - Err(e) => return Err(e), + Incomplete(s) => return Incomplete(s), + Error(e) => return Error(e), } } }, - _ => return Err(Err::Error(error_position!(input, ErrorKind::Custom(5 /* FIXME */)))), + _ => return Error(error_position!(ErrorKind::Custom(5 /* FIXME */), input)), }, _ => s.push(c), } } - Err(Err::Error(error_position!(input, ErrorKind::Custom(3 /* FIXME */)))) + Error(error_position!(ErrorKind::Custom(3 /* FIXME */), input)) } named!(string_lit<&str, String>, delimited!(tag!("\""), string_lit_inner, tag!("\""))); @@ -318,26 +322,30 @@ impl<'input> Lexer<'input> { } impl<'input> Iterator for Lexer<'input> { - type Item = Spanned<Tok<'input>, usize, LexicalError<'input>>; + type Item = Spanned<Tok<'input>, usize, LexicalError>; fn next(&mut self) -> Option<Self::Item> { + use nom::IResult::*; self.skip_comments_and_whitespace(); let input = self.current_input(); if input.is_empty() { return None; } match token(input) { - Ok((rest, t)) => { + Done(rest, t) => { let parsed_len = input.len() - rest.len(); //println!("parsed {} bytes => {:?}", parsed_len, t); let start = self.offset; self.offset += parsed_len; Some(Ok((start, t, self.offset))) } - Err(e) => { + Error(e) => { let offset = self.offset; - // self.offset = self.input.len(); - Some(Err(LexicalError(offset, e))) + self.offset = self.input.len(); + Some(Err(LexicalError::Error(offset, e))) + } + Incomplete(needed) => { + Some(Err(LexicalError::Incomplete(needed))) } } } @@ -346,12 +354,6 @@ impl<'input> Iterator for Lexer<'input> { #[test] fn test_lex() { use self::Tok::*; - let s = "22"; - let expected = [Lambda, Bool(false)]; - let lexer = Lexer::new(s); - let tokens = lexer.map(|r| r.unwrap().1).collect::<Vec<_>>(); - assert_eq!(&tokens, &expected); - let s = "λ(b : Bool) → b == False"; let expected = [Lambda, ParenL, @@ -367,9 +369,9 @@ fn test_lex() { let tokens = lexer.map(|r| r.unwrap().1).collect::<Vec<_>>(); assert_eq!(&tokens, &expected); - assert_eq!(string_lit(r#""a\&b""#), Ok(("", "ab".to_owned()))); - assert_eq!(string_lit(r#""a\ \b""#), Ok(("", "ab".to_owned()))); + assert_eq!(string_lit(r#""a\&b""#).to_result(), Ok("ab".to_owned())); + assert_eq!(string_lit(r#""a\ \b""#).to_result(), Ok("ab".to_owned())); assert!(string_lit(r#""a\ b""#).is_err()); - assert_eq!(string_lit(r#""a\nb""#), Ok(("", "a\nb".to_owned()))); - assert_eq!(string_lit(r#""\o141\x62\99""#), Ok(("", "abd".to_owned()))); + assert_eq!(string_lit(r#""a\nb""#).to_result(), Ok("a\nb".to_owned())); + assert_eq!(string_lit(r#""\o141\x62\99""#).to_result(), Ok("abc".to_owned())); } |