diff options
Diffstat (limited to 'dhall/src/lexer.rs')
| -rw-r--r-- | dhall/src/lexer.rs | 108 |
1 files changed, 66 insertions, 42 deletions
diff --git a/dhall/src/lexer.rs b/dhall/src/lexer.rs index b5cbe6b..5fc0f05 100644 --- a/dhall/src/lexer.rs +++ b/dhall/src/lexer.rs @@ -1,8 +1,8 @@ use nom::*; -use crate::core::Const; use crate::core::Builtin; use crate::core::Builtin::*; +use crate::core::Const; #[derive(Debug, Clone, PartialEq, Eq)] pub enum Keyword { @@ -74,11 +74,13 @@ fn is_identifier_rest_char(c: char) -> bool { macro_rules! digits { ($i:expr, $t:tt, $radix:expr) => {{ - let r: nom::IResult<&str, $t> = - map_res!($i, take_while1_s!(call!(|c: char| c.is_digit($radix))), - |s| $t::from_str_radix(s, $radix)); + let r: nom::IResult<&str, $t> = map_res!( + $i, + take_while1_s!(call!(|c: char| c.is_digit($radix))), + |s| $t::from_str_radix(s, $radix) + ); r - }} + }}; } named!(natural<&str, usize>, digits!(usize, 10)); @@ -105,29 +107,32 @@ macro_rules! ident_tag { if s == $tag { nom::IResult::Done(i, s) } else { - nom::IResult::Error(error_position!(nom::ErrorKind::Tag, $i)) + nom::IResult::Error(error_position!( + nom::ErrorKind::Tag, + $i + )) } } r => r, } - } + }; } fn string_escape_single(c: char) -> Option<&'static str> { match c { - 'n' => Some("\n"), - 'r' => Some("\r"), - 't' => Some("\t"), - '"' => Some("\""), + 'n' => Some("\n"), + 'r' => Some("\r"), + 't' => Some("\t"), + '"' => Some("\""), '\'' => Some("'"), '\\' => Some("\\"), - '0' => Some("\0"), - 'a' => Some("\x07"), - 'b' => Some("\x08"), - 'f' => Some("\x0c"), - 'v' => Some("\x0b"), - '&' => Some(""), - _ => None, + '0' => Some("\0"), + 'a' => Some("\x07"), + 'b' => Some("\x08"), + 'f' => Some("\x0c"), + 'v' => Some("\x0b"), + '&' => Some(""), + _ => None, } } @@ -138,41 +143,53 @@ 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::IResult::*;; use nom::ErrorKind; + use nom::IResult::*; ; let mut s = String::new(); let mut cs = input.char_indices().peekable(); - while let Some((i, c)) = cs.next() { + while let Some((i, c)) = cs.next() { match c { '"' => 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) { + while cs.peek().map(|&(_, s)| s.is_whitespace()) + == Some(true) + { let _ = cs.next(); } if cs.next().map(|p| p.1) != Some('\\') { - return Error(error_position!(ErrorKind::Custom(4 /* FIXME */), input)); + return Error(error_position!( + ErrorKind::Custom(4 /* FIXME */), + input + )); } } Some((j, ec)) => { if let Some(esc) = string_escape_single(ec) { s.push_str(esc); - // FIXME Named ASCII escapes and control character escapes + // FIXME Named ASCII escapes and control character escapes } else { match string_escape_numeric(&input[j..]) { 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(); } + for _ in 0..consumed { + let _ = cs.next(); + } s.push(esc); } Incomplete(s) => return Incomplete(s), Error(e) => return Error(e), } } - }, - _ => return Error(error_position!(ErrorKind::Custom(5 /* FIXME */), input)), + } + _ => { + return Error(error_position!( + ErrorKind::Custom(5 /* FIXME */), + input + )); + } }, _ => s.push(c), } @@ -303,7 +320,8 @@ impl<'input> Lexer<'input> { "{-" => find_end(input, "-}"), "--" => find_end(input, "\n"), // Also skips past \r\n (CRLF) _ => None, - }.unwrap_or(0); + } + .unwrap_or(0); // println!("skipped {} bytes of comment", skip); self.offset += skip; skip != 0 @@ -337,9 +355,7 @@ impl<'input> Iterator for Lexer<'input> { self.offset = self.input.len(); Some(Err(LexicalError::Error(offset, e))) } - Incomplete(needed) => { - Some(Err(LexicalError::Incomplete(needed))) - } + Incomplete(needed) => Some(Err(LexicalError::Incomplete(needed))), } } } @@ -348,23 +364,31 @@ impl<'input> Iterator for Lexer<'input> { fn test_lex() { use self::Tok::*; let s = "λ(b : Bool) → b == False"; - let expected = [Lambda, - ParenL, - Identifier("b"), - Ascription, - Builtin(crate::core::Builtin::Bool), - ParenR, - Arrow, - Identifier("b"), - CompareEQ, - Bool(false)]; + let expected = [ + Lambda, + ParenL, + Identifier("b"), + Ascription, + Builtin(crate::core::Builtin::Bool), + ParenR, + Arrow, + Identifier("b"), + CompareEQ, + Bool(false), + ]; let lexer = Lexer::new(s); let tokens = lexer.map(|r| r.unwrap().1).collect::<Vec<_>>(); assert_eq!(&tokens, &expected); 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_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""#).to_result(), Ok("a\nb".to_owned())); - assert_eq!(string_lit(r#""\o141\x62\99""#).to_result(), Ok("abc".to_owned())); + assert_eq!( + string_lit(r#""\o141\x62\99""#).to_result(), + Ok("abc".to_owned()) + ); } |