David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 1 | //! Adapted from [`nom`](https://github.com/Geal/nom). |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 2 | |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 3 | use std::str::{Chars, CharIndices, Bytes}; |
| 4 | |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 5 | use unicode_xid::UnicodeXID; |
| 6 | |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 7 | use imp::LexError; |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 8 | |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 9 | #[derive(Copy, Clone, Eq, PartialEq)] |
| 10 | pub struct Cursor<'a> { |
| 11 | pub rest: &'a str, |
| 12 | pub off: u32, |
| 13 | } |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 14 | |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 15 | impl<'a> Cursor<'a> { |
| 16 | pub fn advance(&self, amt: usize) -> Cursor<'a> { |
| 17 | Cursor { |
| 18 | rest: &self.rest[amt..], |
| 19 | off: self.off + (amt as u32), |
| 20 | } |
| 21 | } |
| 22 | |
| 23 | pub fn find(&self, p: char) -> Option<usize> { |
| 24 | self.rest.find(p) |
| 25 | } |
| 26 | |
| 27 | pub fn starts_with(&self, s: &str) -> bool { |
| 28 | self.rest.starts_with(s) |
| 29 | } |
| 30 | |
| 31 | pub fn is_empty(&self) -> bool { |
| 32 | self.rest.is_empty() |
| 33 | } |
| 34 | |
| 35 | pub fn len(&self) -> usize { |
| 36 | self.rest.len() |
| 37 | } |
| 38 | |
| 39 | pub fn as_bytes(&self) -> &'a [u8] { |
| 40 | self.rest.as_bytes() |
| 41 | } |
| 42 | |
| 43 | pub fn bytes(&self) -> Bytes<'a> { |
| 44 | self.rest.bytes() |
| 45 | } |
| 46 | |
| 47 | pub fn chars(&self) -> Chars<'a> { |
| 48 | self.rest.chars() |
| 49 | } |
| 50 | |
| 51 | pub fn char_indices(&self) -> CharIndices<'a> { |
| 52 | self.rest.char_indices() |
| 53 | } |
| 54 | } |
| 55 | |
| 56 | pub type PResult<'a, O> = Result<(Cursor<'a>, O), LexError>; |
| 57 | |
| 58 | pub fn whitespace(input: Cursor) -> PResult<()> { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 59 | if input.is_empty() { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 60 | return Err(LexError); |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 61 | } |
| 62 | |
| 63 | let bytes = input.as_bytes(); |
| 64 | let mut i = 0; |
| 65 | while i < bytes.len() { |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 66 | let s = input.advance(i); |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 67 | if bytes[i] == b'/' { |
| 68 | if s.starts_with("//") && (!s.starts_with("///") || s.starts_with("////")) && |
| 69 | !s.starts_with("//!") { |
| 70 | if let Some(len) = s.find('\n') { |
| 71 | i += len + 1; |
| 72 | continue; |
| 73 | } |
| 74 | break; |
| 75 | } else if s.starts_with("/*") && (!s.starts_with("/**") || s.starts_with("/***")) && |
| 76 | !s.starts_with("/*!") { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 77 | let (_, com) = block_comment(s)?; |
| 78 | i += com.len(); |
| 79 | continue; |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 80 | } |
| 81 | } |
| 82 | match bytes[i] { |
| 83 | b' ' | 0x09...0x0d => { |
| 84 | i += 1; |
| 85 | continue; |
| 86 | } |
| 87 | b if b <= 0x7f => {} |
| 88 | _ => { |
| 89 | let ch = s.chars().next().unwrap(); |
| 90 | if is_whitespace(ch) { |
| 91 | i += ch.len_utf8(); |
| 92 | continue; |
| 93 | } |
| 94 | } |
| 95 | } |
| 96 | return if i > 0 { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 97 | Ok((s, ())) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 98 | } else { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 99 | Err(LexError) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 100 | }; |
| 101 | } |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 102 | Ok((input.advance(input.len()), ())) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 103 | } |
| 104 | |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 105 | pub fn block_comment(input: Cursor) -> PResult<&str> { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 106 | if !input.starts_with("/*") { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 107 | return Err(LexError); |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 108 | } |
| 109 | |
| 110 | let mut depth = 0; |
| 111 | let bytes = input.as_bytes(); |
| 112 | let mut i = 0; |
| 113 | let upper = bytes.len() - 1; |
| 114 | while i < upper { |
| 115 | if bytes[i] == b'/' && bytes[i + 1] == b'*' { |
| 116 | depth += 1; |
| 117 | i += 1; // eat '*' |
| 118 | } else if bytes[i] == b'*' && bytes[i + 1] == b'/' { |
| 119 | depth -= 1; |
| 120 | if depth == 0 { |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 121 | return Ok((input.advance(i + 2), &input.rest[..i + 2])); |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 122 | } |
| 123 | i += 1; // eat '/' |
| 124 | } |
| 125 | i += 1; |
| 126 | } |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 127 | Err(LexError) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 128 | } |
| 129 | |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 130 | pub fn skip_whitespace(input: Cursor) -> Cursor { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 131 | match whitespace(input) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 132 | Ok((rest, _)) => rest, |
| 133 | Err(LexError) => input, |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 134 | } |
| 135 | } |
| 136 | |
| 137 | fn is_whitespace(ch: char) -> bool { |
| 138 | // Rust treats left-to-right mark and right-to-left mark as whitespace |
| 139 | ch.is_whitespace() || ch == '\u{200e}' || ch == '\u{200f}' |
| 140 | } |
| 141 | |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 142 | pub fn word_break(input: Cursor) -> PResult<()> { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 143 | match input.chars().next() { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 144 | Some(ch) if UnicodeXID::is_xid_continue(ch) => Err(LexError), |
| 145 | Some(_) | None => Ok((input, ())), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 146 | } |
| 147 | } |
| 148 | |
| 149 | macro_rules! named { |
| 150 | ($name:ident -> $o:ty, $submac:ident!( $($args:tt)* )) => { |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 151 | fn $name<'a>(i: Cursor<'a>) -> $crate::strnom::PResult<'a, $o> { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 152 | $submac!(i, $($args)*) |
| 153 | } |
| 154 | }; |
| 155 | } |
| 156 | |
| 157 | macro_rules! alt { |
| 158 | ($i:expr, $e:ident | $($rest:tt)*) => { |
| 159 | alt!($i, call!($e) | $($rest)*) |
| 160 | }; |
| 161 | |
| 162 | ($i:expr, $subrule:ident!( $($args:tt)*) | $($rest:tt)*) => { |
| 163 | match $subrule!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 164 | res @ Ok(_) => res, |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 165 | _ => alt!($i, $($rest)*) |
| 166 | } |
| 167 | }; |
| 168 | |
| 169 | ($i:expr, $subrule:ident!( $($args:tt)* ) => { $gen:expr } | $($rest:tt)+) => { |
| 170 | match $subrule!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 171 | Ok((i, o)) => Ok((i, $gen(o))), |
| 172 | Err(LexError) => alt!($i, $($rest)*) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 173 | } |
| 174 | }; |
| 175 | |
| 176 | ($i:expr, $e:ident => { $gen:expr } | $($rest:tt)*) => { |
| 177 | alt!($i, call!($e) => { $gen } | $($rest)*) |
| 178 | }; |
| 179 | |
| 180 | ($i:expr, $e:ident => { $gen:expr }) => { |
| 181 | alt!($i, call!($e) => { $gen }) |
| 182 | }; |
| 183 | |
| 184 | ($i:expr, $subrule:ident!( $($args:tt)* ) => { $gen:expr }) => { |
| 185 | match $subrule!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 186 | Ok((i, o)) => Ok((i, $gen(o))), |
| 187 | Err(LexError) => Err(LexError), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 188 | } |
| 189 | }; |
| 190 | |
| 191 | ($i:expr, $e:ident) => { |
| 192 | alt!($i, call!($e)) |
| 193 | }; |
| 194 | |
| 195 | ($i:expr, $subrule:ident!( $($args:tt)*)) => { |
| 196 | $subrule!($i, $($args)*) |
| 197 | }; |
| 198 | } |
| 199 | |
| 200 | macro_rules! do_parse { |
| 201 | ($i:expr, ( $($rest:expr),* )) => { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 202 | Ok(($i, ( $($rest),* ))) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 203 | }; |
| 204 | |
| 205 | ($i:expr, $e:ident >> $($rest:tt)*) => { |
| 206 | do_parse!($i, call!($e) >> $($rest)*) |
| 207 | }; |
| 208 | |
| 209 | ($i:expr, $submac:ident!( $($args:tt)* ) >> $($rest:tt)*) => { |
| 210 | match $submac!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 211 | Err(LexError) => Err(LexError), |
| 212 | Ok((i, _)) => do_parse!(i, $($rest)*), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 213 | } |
| 214 | }; |
| 215 | |
| 216 | ($i:expr, $field:ident : $e:ident >> $($rest:tt)*) => { |
| 217 | do_parse!($i, $field: call!($e) >> $($rest)*) |
| 218 | }; |
| 219 | |
| 220 | ($i:expr, $field:ident : $submac:ident!( $($args:tt)* ) >> $($rest:tt)*) => { |
| 221 | match $submac!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 222 | Err(LexError) => Err(LexError), |
| 223 | Ok((i, o)) => { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 224 | let $field = o; |
| 225 | do_parse!(i, $($rest)*) |
| 226 | }, |
| 227 | } |
| 228 | }; |
| 229 | } |
| 230 | |
| 231 | macro_rules! peek { |
| 232 | ($i:expr, $submac:ident!( $($args:tt)* )) => { |
| 233 | match $submac!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 234 | Ok((_, o)) => Ok(($i, o)), |
| 235 | Err(LexError) => Err(LexError), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 236 | } |
| 237 | }; |
| 238 | } |
| 239 | |
| 240 | macro_rules! call { |
| 241 | ($i:expr, $fun:expr $(, $args:expr)*) => { |
| 242 | $fun($i $(, $args)*) |
| 243 | }; |
| 244 | } |
| 245 | |
| 246 | macro_rules! option { |
| 247 | ($i:expr, $f:expr) => { |
| 248 | match $f($i) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 249 | Ok((i, o)) => Ok((i, Some(o))), |
| 250 | Err(LexError) => Ok(($i, None)), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 251 | } |
| 252 | }; |
| 253 | } |
| 254 | |
| 255 | macro_rules! take_until { |
| 256 | ($i:expr, $substr:expr) => {{ |
| 257 | if $substr.len() > $i.len() { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 258 | Err(LexError) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 259 | } else { |
| 260 | let substr_vec: Vec<char> = $substr.chars().collect(); |
| 261 | let mut window: Vec<char> = vec![]; |
| 262 | let mut offset = $i.len(); |
| 263 | let mut parsed = false; |
| 264 | for (o, c) in $i.char_indices() { |
| 265 | window.push(c); |
| 266 | if window.len() > substr_vec.len() { |
| 267 | window.remove(0); |
| 268 | } |
| 269 | if window == substr_vec { |
| 270 | parsed = true; |
| 271 | window.pop(); |
| 272 | let window_len: usize = window.iter() |
| 273 | .map(|x| x.len_utf8()) |
| 274 | .fold(0, |x, y| x + y); |
| 275 | offset = o - window_len; |
| 276 | break; |
| 277 | } |
| 278 | } |
| 279 | if parsed { |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 280 | Ok(($i.advance(offset), &$i.rest[..offset])) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 281 | } else { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 282 | Err(LexError) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 283 | } |
| 284 | } |
| 285 | }}; |
| 286 | } |
| 287 | |
| 288 | macro_rules! tuple { |
| 289 | ($i:expr, $($rest:tt)*) => { |
| 290 | tuple_parser!($i, (), $($rest)*) |
| 291 | }; |
| 292 | } |
| 293 | |
| 294 | /// Do not use directly. Use `tuple!`. |
| 295 | macro_rules! tuple_parser { |
| 296 | ($i:expr, ($($parsed:tt),*), $e:ident, $($rest:tt)*) => { |
| 297 | tuple_parser!($i, ($($parsed),*), call!($e), $($rest)*) |
| 298 | }; |
| 299 | |
| 300 | ($i:expr, (), $submac:ident!( $($args:tt)* ), $($rest:tt)*) => { |
| 301 | match $submac!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 302 | Err(LexError) => Err(LexError), |
| 303 | Ok((i, o)) => tuple_parser!(i, (o), $($rest)*), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 304 | } |
| 305 | }; |
| 306 | |
| 307 | ($i:expr, ($($parsed:tt)*), $submac:ident!( $($args:tt)* ), $($rest:tt)*) => { |
| 308 | match $submac!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 309 | Err(LexError) => Err(LexError), |
| 310 | Ok((i, o)) => tuple_parser!(i, ($($parsed)* , o), $($rest)*), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 311 | } |
| 312 | }; |
| 313 | |
| 314 | ($i:expr, ($($parsed:tt),*), $e:ident) => { |
| 315 | tuple_parser!($i, ($($parsed),*), call!($e)) |
| 316 | }; |
| 317 | |
| 318 | ($i:expr, (), $submac:ident!( $($args:tt)* )) => { |
| 319 | $submac!($i, $($args)*) |
| 320 | }; |
| 321 | |
| 322 | ($i:expr, ($($parsed:expr),*), $submac:ident!( $($args:tt)* )) => { |
| 323 | match $submac!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 324 | Err(LexError) => Err(LexError), |
| 325 | Ok((i, o)) => Ok((i, ($($parsed),*, o))) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 326 | } |
| 327 | }; |
| 328 | |
| 329 | ($i:expr, ($($parsed:expr),*)) => { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 330 | Ok(($i, ($($parsed),*))) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 331 | }; |
| 332 | } |
| 333 | |
| 334 | macro_rules! not { |
| 335 | ($i:expr, $submac:ident!( $($args:tt)* )) => { |
| 336 | match $submac!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 337 | Ok((_, _)) => Err(LexError), |
| 338 | Err(LexError) => Ok(($i, ())), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 339 | } |
| 340 | }; |
| 341 | } |
| 342 | |
| 343 | macro_rules! tag { |
| 344 | ($i:expr, $tag:expr) => { |
| 345 | if $i.starts_with($tag) { |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 346 | Ok(($i.advance($tag.len()), &$i.rest[..$tag.len()])) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 347 | } else { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 348 | Err(LexError) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 349 | } |
| 350 | }; |
| 351 | } |
| 352 | |
| 353 | macro_rules! punct { |
| 354 | ($i:expr, $punct:expr) => { |
| 355 | $crate::strnom::punct($i, $punct) |
| 356 | }; |
| 357 | } |
| 358 | |
| 359 | /// Do not use directly. Use `punct!`. |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 360 | pub fn punct<'a>(input: Cursor<'a>, token: &'static str) -> PResult<'a, &'a str> { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 361 | let input = skip_whitespace(input); |
| 362 | if input.starts_with(token) { |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 363 | Ok((input.advance(token.len()), token)) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 364 | } else { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 365 | Err(LexError) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 366 | } |
| 367 | } |
| 368 | |
| 369 | macro_rules! keyword { |
| 370 | ($i:expr, $keyword:expr) => { |
| 371 | $crate::strnom::keyword($i, $keyword) |
| 372 | }; |
| 373 | } |
| 374 | |
| 375 | /// Do not use directly. Use `keyword!`. |
Nika Layzell | f8d5f21 | 2017-12-11 14:07:02 -0500 | [diff] [blame] | 376 | pub fn keyword<'a>(input: Cursor<'a>, token: &'static str) -> PResult<'a, &'a str> { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 377 | match punct(input, token) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 378 | Ok((rest, _)) => { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 379 | match word_break(rest) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 380 | Ok((_, _)) => Ok((rest, token)), |
| 381 | Err(LexError) => Err(LexError), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 382 | } |
| 383 | } |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 384 | Err(LexError) => Err(LexError), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 385 | } |
| 386 | } |
| 387 | |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 388 | macro_rules! preceded { |
| 389 | ($i:expr, $submac:ident!( $($args:tt)* ), $submac2:ident!( $($args2:tt)* )) => { |
| 390 | match tuple!($i, $submac!($($args)*), $submac2!($($args2)*)) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 391 | Ok((remaining, (_, o))) => Ok((remaining, o)), |
| 392 | Err(LexError) => Err(LexError), |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 393 | } |
| 394 | }; |
| 395 | |
| 396 | ($i:expr, $submac:ident!( $($args:tt)* ), $g:expr) => { |
| 397 | preceded!($i, $submac!($($args)*), call!($g)) |
| 398 | }; |
| 399 | } |
| 400 | |
| 401 | macro_rules! delimited { |
| 402 | ($i:expr, $submac:ident!( $($args:tt)* ), $($rest:tt)+) => { |
| 403 | match tuple_parser!($i, (), $submac!($($args)*), $($rest)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 404 | Err(LexError) => Err(LexError), |
| 405 | Ok((i1, (_, o, _))) => Ok((i1, o)) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 406 | } |
| 407 | }; |
| 408 | } |
| 409 | |
| 410 | macro_rules! map { |
| 411 | ($i:expr, $submac:ident!( $($args:tt)* ), $g:expr) => { |
| 412 | match $submac!($i, $($args)*) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 413 | Err(LexError) => Err(LexError), |
| 414 | Ok((i, o)) => Ok((i, call!(o, $g))) |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 415 | } |
| 416 | }; |
| 417 | |
| 418 | ($i:expr, $f:expr, $g:expr) => { |
| 419 | map!($i, call!($f), $g) |
| 420 | }; |
| 421 | } |
| 422 | |
| 423 | macro_rules! many0 { |
| 424 | ($i:expr, $f:expr) => {{ |
| 425 | let ret; |
| 426 | let mut res = ::std::vec::Vec::new(); |
| 427 | let mut input = $i; |
| 428 | |
| 429 | loop { |
| 430 | if input.is_empty() { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 431 | ret = Ok((input, res)); |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 432 | break; |
| 433 | } |
| 434 | |
| 435 | match $f(input) { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 436 | Err(LexError) => { |
| 437 | ret = Ok((input, res)); |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 438 | break; |
| 439 | } |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 440 | Ok((i, o)) => { |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 441 | // loop trip must always consume (otherwise infinite loops) |
| 442 | if i.len() == input.len() { |
David Tolnay | 1218e12 | 2017-06-01 11:13:45 -0700 | [diff] [blame] | 443 | ret = Err(LexError); |
David Tolnay | b103266 | 2017-05-31 15:52:28 -0700 | [diff] [blame] | 444 | break; |
| 445 | } |
| 446 | |
| 447 | res.push(o); |
| 448 | input = i; |
| 449 | } |
| 450 | } |
| 451 | } |
| 452 | |
| 453 | ret |
| 454 | }}; |
| 455 | } |