1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005
//! Extensions to the nom [`Parser`][nom::Parser] trait which add postfix //! versions of the common combinators. See [`ParserExt`] for details. use std::{marker::PhantomData, ops::RangeTo, str::FromStr}; use nom::{ error::{ContextError, ErrorKind as NomErrorKind, FromExternalError, ParseError}, Err as NomErr, InputLength, Offset, Parser, Slice, }; /// Additional postfix parser combinators, as a complement to [`Parser`]. /// Mostly these are postfix versions of the combinators in [`nom::combinator`] /// and [`nom::sequence`], with some additional combinators original to /// `nom-supreme`. /// /// Compatibility note: it is expected that eventually many of these postfix /// methods will eventually be added directly to the [`Parser`] trait. It will /// therefore *not* be considered a compatibility break to remove those methods /// from [`ParserExt`], *if* they have the same name and signature. pub trait ParserExt<I, O, E>: Parser<I, O, E> + Sized { /// Borrow a parser. This allows building parser combinators while still /// retaining ownership of the original parser. This is necessary because /// `impl<T: Parser> Parser for &mut T` is impossible due to conflicts /// with `impl<T: FnMut> Parser for T`. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = tag("Hello"); /// /// let mut subparser = parser.by_ref().terminated(tag(", World")); /// /// assert_eq!(subparser.parse("Hello, World!"), Ok(("!", "Hello"))); /// assert_eq!( /// subparser.parse("Hello"), /// Err(Err::Error(Error{input: "", code: ErrorKind::Tag})) /// ); /// /// // We still have ownership of the original parser /// /// assert_eq!(parser.parse("Hello, World!"), Ok((", World!", "Hello"))); /// assert_eq!(parser.parse("Hello"), Ok(("", "Hello"))); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn by_ref(&mut self) -> RefParser<Self> { RefParser { parser: self } } /// Create a parser that must consume all of the input, or else return an /// error. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = tag("Hello").all_consuming(); /// /// assert_eq!(parser.parse("Hello"), Ok(("", "Hello"))); /// assert_eq!( /// parser.parse("World"), /// Err(Err::Error(Error{input: "World", code: ErrorKind::Tag})) /// ); /// assert_eq!( /// parser.parse("Hello World"), /// Err(Err::Error(Error{input: " World", code: ErrorKind::Eof})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn all_consuming(self) -> AllConsuming<Self> where I: InputLength, E: ParseError<I>, { AllConsuming { parser: self } } /// Create a parser that transforms `Incomplete` into `Error`. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::streaming::tag; /// /// let mut parser = tag("Hello").complete(); /// /// assert_eq!(parser.parse("Hello"), Ok(("", "Hello"))); /// assert_eq!( /// parser.parse("World"), /// Err(Err::Error(Error{input: "World", code: ErrorKind::Tag})) /// ); /// assert_eq!( /// parser.parse("Hel"), /// Err(Err::Error(Error{input: "Hel", code: ErrorKind::Complete})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn complete(self) -> Complete<Self> where I: Clone, E: ParseError<I>, { Complete { parser: self } } /// Create a parser that transforms `Error` into `Failure`. This will /// end the parse immediately, even if there are other branches that /// could occur. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = tag("Hello").cut(); /// /// assert_eq!(parser.parse("Hello"), Ok(("", "Hello"))); /// assert_eq!( /// parser.parse("World"), /// Err(Err::Failure(Error{input: "World", code: ErrorKind::Tag})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn cut(self) -> Cut<Self> { Cut { parser: self } } /// Create a parser that applies a mapping function `func` to the output /// of the subparser. Any errors from `func` will be transformed into /// parse errors via [`FromExternalError`]. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom::character::complete::alphanumeric1; /// use nom_supreme::parser_ext::ParserExt; /// /// let mut parser = alphanumeric1.map_res(|s: &str| s.parse()); /// /// assert_eq!(parser.parse("10 abc"), Ok((" abc", 10))); /// assert_eq!( /// parser.parse("<===>"), /// Err(Err::Error(Error{input: "<===>", code: ErrorKind::AlphaNumeric})), /// ); /// assert_eq!( /// parser.parse("abc abc"), /// Err(Err::Error(Error{input: "abc abc", code: ErrorKind::MapRes})), /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn map_res<F, O2, E2>(self, func: F) -> MapRes<Self, F, O, E2> where F: FnMut(O) -> Result<O2, E2>, E: FromExternalError<I, E2>, I: Clone, { MapRes { parser: self, func, phantom: PhantomData, } } /// Make this parser optional; if it fails to parse, instead it returns /// `None` with the input in the original position. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser, IResult}; /// # use nom::error::{Error, ErrorKind}; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// fn parser(input: &str) -> IResult<&str, Option<&str>> { /// tag("Hello").opt().parse(input) /// } /// /// assert_eq!(parser.parse("Hello, World"), Ok((", World", Some("Hello")))); /// assert_eq!(parser.parse("World"), Ok(("World", None))); /// /// let mut parser = tag("Hello").cut().opt(); /// assert_eq!( /// parser.parse("World"), /// Err(Err::Failure(Error{input: "World", code: ErrorKind::Tag})) /// ) /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn opt(self) -> Optional<Self> where I: Clone, { Optional { parser: self } } /// Replace this parser's output with the entire input that was consumed /// by the parser. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom::character::complete::space1; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = tag("Hello").delimited_by(space1).recognize(); /// /// assert_eq!(parser.parse(" Hello World!"), Ok(("World!", " Hello "))); /// assert_eq!( /// parser.parse("Hello"), /// Err(Err::Error(Error{input: "Hello", code: ErrorKind::Space})) /// ) /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn recognize(self) -> Recognize<Self, O> where I: Clone + Slice<RangeTo<usize>> + Offset, { Recognize { parser: self, phantom: PhantomData, } } /// Replace this parser's output with a clone of `value` every time it /// finishes successfully. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom::branch::alt; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// use nom_supreme::error::{ErrorTree, BaseErrorKind, Expectation}; /// /// /// let mut parser = alt(( /// tag("true").value(true), /// tag("false").value(false), /// )); /// /// assert_eq!(parser.parse("true abc").unwrap(), (" abc", true)); /// assert_eq!(parser.parse("false abc").unwrap(), (" abc", false)); /// /// // ErrorTree gives much better error reports for alt and tag. /// let err = parser.parse("null").unwrap_err(); /// let choices = match err { /// Err::Error(ErrorTree::Alt(choices)) => choices, /// _ => panic!("Unexpected error {:?}", err) /// }; /// assert!(matches!( /// choices.as_slice(), /// [ /// ErrorTree::Base { /// kind: BaseErrorKind::Expected(Expectation::Tag("true")), /// location: "null", /// }, /// ErrorTree::Base { /// kind: BaseErrorKind::Expected(Expectation::Tag("false")), /// location: "null", /// }, /// ] /// )) /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn value<T: Clone>(self, value: T) -> Value<T, Self, O> { Value { parser: self, value, phantom: PhantomData, } } /// Require the output of this parser to pass a verifier function, or /// else return a parse error. /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom::character::complete::alpha1; /// use nom_supreme::parser_ext::ParserExt; /// /// let mut parser = alpha1.verify(|s: &&str| s.len() == 5); /// /// assert_eq!(parser.parse("Hello"), Ok(("", "Hello"))); /// assert_eq!(parser.parse("Hello, World"), Ok((", World", "Hello"))); /// assert_eq!( /// parser.parse("abc"), /// Err(Err::Error(Error{input: "abc", code: ErrorKind::Verify})) /// ); /// assert_eq!( /// parser.parse("abcabcabc"), /// Err(Err::Error(Error{input: "abcabcabc", code: ErrorKind::Verify})) /// ); /// assert_eq!( /// parser.parse("123"), /// Err(Err::Error(Error{input: "123", code: ErrorKind::Alpha})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn verify<F>(self, verifier: F) -> Verify<Self, F> where F: Fn(&O) -> bool, I: Clone, E: ParseError<I>, { Verify { parser: self, verifier, } } /// Add some context to the parser. This context will be added to any /// errors that are returned from the parser via [`ContextError`]. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{VerboseError, ErrorKind, VerboseErrorKind}; /// use nom::sequence::separated_pair; /// use nom::character::complete::space1; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = separated_pair( /// tag("Hello").context("hello"), /// space1, /// tag("World").context("world"), /// ) /// .context("hello world"); /// /// assert_eq!(parser.parse("Hello World"), Ok(("", ("Hello", "World")))); /// assert_eq!( /// parser.parse("Hel"), /// Err(Err::Error(VerboseError {errors: vec![ /// ("Hel", VerboseErrorKind::Nom(ErrorKind::Tag)), /// ("Hel", VerboseErrorKind::Context("hello")), /// ("Hel", VerboseErrorKind::Context("hello world")), /// ]})) /// ); /// assert_eq!( /// parser.parse("Hello"), /// Err(Err::Error(VerboseError {errors: vec![ /// ("", VerboseErrorKind::Nom(ErrorKind::Space)), /// ("Hello", VerboseErrorKind::Context("hello world")), /// ]})) /// ); /// assert_eq!( /// parser.parse("Hello Wor"), /// Err(Err::Error(VerboseError {errors: vec![ /// ("Wor", VerboseErrorKind::Nom(ErrorKind::Tag)), /// ("Wor", VerboseErrorKind::Context("world")), /// ("Hello Wor", VerboseErrorKind::Context("hello world")), /// ]})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn context(self, context: &'static str) -> Context<Self> where E: ContextError<I>, I: Clone, { Context { context, parser: self, } } /// Add a terminator parser. The terminator will run after this parser, /// returning any errors, but its output will otherwise be discarded. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = tag("Hello").terminated(tag(" World")); /// /// assert_eq!(parser.parse("Hello World!"), Ok(("!", "Hello"))); /// assert_eq!( /// parser.parse("Hello"), /// Err(Err::Error(Error{input: "", code: ErrorKind::Tag})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn terminated<F, O2>(self, terminator: F) -> Terminated<Self, F, O2> where F: Parser<I, O2, E>, { Terminated { parser: self, terminator, phantom: PhantomData, } } /// Make this parser precede another one. The successor parser will run /// after this one succeeds, and the successor's output will be returned. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom::character::complete::digit1; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = tag("Value: ").precedes(digit1); /// /// assert_eq!(parser.parse("Value: 25;"), Ok((";", "25"))); /// assert_eq!( /// parser.parse("Value: "), /// Err(Err::Error(Error{input: "", code: ErrorKind::Digit})) /// ); /// assert_eq!( /// parser.parse("25"), /// Err(Err::Error(Error{input: "25", code: ErrorKind::Tag})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn precedes<F, O2>(self, successor: F) -> Preceded<F, Self, O> where F: Parser<I, O2, E>, { successor.preceded_by(self) } /// Make this parser preceded by another one. The `prefix` will run first, /// and if it succeeds, its output will be discard and this parser will /// be run. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom::character::complete::digit1; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = digit1.preceded_by(tag("Value: ")); /// /// assert_eq!(parser.parse("Value: 25;"), Ok((";", "25"))); /// assert_eq!( /// parser.parse("Value: "), /// Err(Err::Error(Error{input: "", code: ErrorKind::Digit})) /// ); /// assert_eq!( /// parser.parse("25"), /// Err(Err::Error(Error{input: "25", code: ErrorKind::Tag})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn preceded_by<F, O2>(self, prefix: F) -> Preceded<Self, F, O2> where F: Parser<I, O2, E>, { Preceded { parser: self, prefix, phantom: PhantomData, } } /// Make this parser delimited, requiring a `delimiter` as both a prefix and /// a suffix. The output of the delimiters is discarded. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom::character::complete::{char, digit1}; /// use nom_supreme::parser_ext::ParserExt; /// /// let mut parser = digit1.delimited_by(char('\'')); /// /// assert_eq!(parser.parse("'123' '456'"), Ok((" '456'", "123"))); /// assert_eq!( /// parser.parse("'' ''"), /// Err(Err::Error(Error{input: "' ''", code: ErrorKind::Digit})) /// ); /// assert_eq!( /// parser.parse("'123 '"), /// Err(Err::Error(Error{input: " '", code: ErrorKind::Char})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn delimited_by<D, O2>(self, delimiter: D) -> Delimited<Self, D, O2> where D: Parser<I, O2, E>, { Delimited { parser: self, delimiter, phantom: PhantomData, } } /// Make this parser peeking: it runs normally but consumes no input. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = tag("Hello").peek(); /// /// assert_eq!(parser.parse("Hello World"), Ok(("Hello World", "Hello"))); /// assert_eq!( /// parser.parse("World"), /// Err(Err::Error(Error{input: "World", code: ErrorKind::Tag})) /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn peek(self) -> Peek<Self> where I: Clone, { Peek { parser: self } } /// Make this parser a negative lookahead: it will succeed if the subparser /// fails, and fail if the subparser succeeds. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser}; /// # use nom::error::{Error, ErrorKind}; /// use nom_supreme::parser_ext::ParserExt; /// use nom_supreme::tag::complete::tag; /// /// let mut parser = tag("Hello").not(); /// /// assert_eq!(parser.parse("World"), Ok(("World", ()))); /// assert_eq!( /// parser.parse("Hello World"), /// Err(Err::Error(Error{input: "Hello World", code: ErrorKind::Not})), /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn not(self) -> Not<Self, O> where I: Clone, E: ParseError<I>, { Not { parser: self, phantom: PhantomData, } } /// Create a parser that parses something via [`FromStr`], using this /// parser as a recognizer for the string to pass to /// [`from_str`][FromStr::from_str]. /// /// # Example /// /// ```rust /// # use nom::{Err, Parser, IResult}; /// # use nom::error::{Error, ErrorKind}; /// use nom::character::complete::digit1; /// use nom_supreme::parser_ext::ParserExt; /// /// let mut parser = digit1.parse_from_str(); /// /// assert_eq!(parser.parse("123 abc"), Ok((" abc", 123))); /// assert_eq!( /// parser.parse("abc"), /// Err(Err::Error(Error{input: "abc", code: ErrorKind::Digit})), /// ); /// ``` #[inline] #[must_use = "Parsers do nothing unless used"] fn parse_from_str<'a, T>(self) -> FromStrParser<Self, T> where Self: Parser<&'a str, &'a str, E>, T: FromStr, E: FromExternalError<&'a str, T::Err>, { FromStrParser { parser: self, phantom: PhantomData, } } } impl<I, O, E, P> ParserExt<I, O, E> for P where P: Parser<I, O, E> {} /// Parser wrapping a mutable reference to a subparser. #[derive(Debug)] pub struct RefParser<'a, P> { parser: &'a mut P, } impl<'a, I, O, E, P> Parser<I, O, E> for RefParser<'a, P> where P: Parser<I, O, E>, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O, E> { self.parser.parse(input) } } /// Parser which returns an error if the subparser didn't consume the whole /// input. #[derive(Debug, Clone, Copy)] pub struct AllConsuming<P> { parser: P, } impl<I, O, E, P> Parser<I, O, E> for AllConsuming<P> where P: Parser<I, O, E>, E: ParseError<I>, I: InputLength, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O, E> { let (tail, value) = self.parser.parse(input)?; if tail.input_len() > 0 { Err(NomErr::Error(E::from_error_kind(tail, NomErrorKind::Eof))) } else { Ok((tail, value)) } } } /// Parser which returns an error if the subparser returned /// [`Incomplete`][nom::Err::Incomplete]. #[derive(Debug, Clone, Copy)] pub struct Complete<P> { parser: P, } impl<I, O, E, P> Parser<I, O, E> for Complete<P> where P: Parser<I, O, E>, E: ParseError<I>, I: Clone, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O, E> { self.parser .parse(input.clone()) .map_err(move |err| match err { NomErr::Incomplete(..) => { NomErr::Error(E::from_error_kind(input, NomErrorKind::Complete)) } err => err, }) } } /// Parser which returns a [`Failure`][nom::Err::Failure] if the subparser /// returned an error. This prevents other branches from being tried. #[derive(Debug, Clone, Copy)] pub struct Cut<P> { parser: P, } impl<I, O, E, P> Parser<I, O, E> for Cut<P> where P: Parser<I, O, E>, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O, E> { self.parser.parse(input).map_err(|err| match err { NomErr::Error(err) => NomErr::Failure(err), err => err, }) } } /// Parser which wraps the subparser output in an [`Option`], and returns a /// successful [`None`] output if it fails. #[derive(Debug, Clone, Copy)] pub struct Optional<P> { parser: P, } impl<I, O, E, P> Parser<I, Option<O>, E> for Optional<P> where P: Parser<I, O, E>, I: Clone, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, Option<O>, E> { match self.parser.parse(input.clone()) { Ok((tail, value)) => Ok((tail, Some(value))), Err(NomErr::Error(_)) => Ok((input, None)), Err(e) => Err(e), } } } /// Parser which, when successful, discards the output of the subparser and /// instead returns the consumed input. #[derive(Debug, Clone, Copy)] pub struct Recognize<P, O> { parser: P, phantom: PhantomData<O>, } impl<I, O, E, P> Parser<I, I, E> for Recognize<P, O> where P: Parser<I, O, E>, I: Clone + Slice<RangeTo<usize>> + Offset, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, I, E> { let (tail, _) = self.parser.parse(input.clone())?; let index = input.offset(&tail); Ok((tail, input.slice(..index))) } } /// Parser which, when successful, discards the output of the subparser and /// instead returns a clone of a value. #[derive(Debug, Clone, Copy)] pub struct Value<T, P, O> { parser: P, value: T, phantom: PhantomData<O>, } impl<I, O, E, T, P> Parser<I, T, E> for Value<T, P, O> where P: Parser<I, O, E>, T: Clone, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, T, E> { let (input, _) = self.parser.parse(input)?; Ok((input, self.value.clone())) } } /// Parser which checks the output of its subparser against a verifier function. #[derive(Debug, Clone, Copy)] pub struct Verify<P, F> { parser: P, verifier: F, } impl<I, O, E, P, F> Parser<I, O, E> for Verify<P, F> where P: Parser<I, O, E>, E: ParseError<I>, F: Fn(&O) -> bool, I: Clone, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O, E> { let (tail, value) = self.parser.parse(input.clone())?; match (self.verifier)(&value) { true => Ok((tail, value)), false => Err(NomErr::Error(E::from_error_kind( input, NomErrorKind::Verify, ))), } } } /// Parser which attaches additional context to any errors returned by the /// subparser. #[derive(Debug, Clone, Copy)] pub struct Context<P> { context: &'static str, parser: P, } impl<I, O, E, P> Parser<I, O, E> for Context<P> where P: Parser<I, O, E>, E: ContextError<I>, I: Clone, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O, E> { self.parser .parse(input.clone()) .map_err(move |err| err.map(move |err| E::add_context(input, self.context, err))) } } /// Parser which gets and discards an output from a second subparser, /// returning the output from the original parser if both were successful. #[derive(Debug, Clone, Copy)] pub struct Terminated<P1, P2, O2> { parser: P1, terminator: P2, phantom: PhantomData<O2>, } impl<I, O1, O2, E, P1, P2> Parser<I, O1, E> for Terminated<P1, P2, O2> where P1: Parser<I, O1, E>, P2: Parser<I, O2, E>, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O1, E> { let (input, value) = self.parser.parse(input)?; let (input, _) = self.terminator.parse(input)?; Ok((input, value)) } } /// Parser which gets and discards an output from a prefix subparser before /// running the main subparser. Returns the output from the main subparser if /// both were successful. #[derive(Debug, Clone, Copy)] pub struct Preceded<P1, P2, O2> { parser: P1, prefix: P2, phantom: PhantomData<O2>, } impl<I, O1, O2, E, P1, P2> Parser<I, O1, E> for Preceded<P1, P2, O2> where P1: Parser<I, O1, E>, P2: Parser<I, O2, E>, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O1, E> { let (input, _) = self.prefix.parse(input)?; self.parser.parse(input) } } /// Parser which gets and discards a delimiting value both before and after the /// main subparser. Returns the output from the main subparser if all were /// successful. #[derive(Debug, Clone, Copy)] pub struct Delimited<P, D, O2> { parser: P, delimiter: D, phantom: PhantomData<O2>, } impl<P, D, I, O, E, O2> Parser<I, O, E> for Delimited<P, D, O2> where P: Parser<I, O, E>, D: Parser<I, O2, E>, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O, E> { let (input, _) = self.delimiter.parse(input)?; let (input, value) = self.parser.parse(input)?; let (input, _) = self.delimiter.parse(input)?; Ok((input, value)) } } /// Parser which runs a fallible mapping function on the output of the /// subparser. Any errors returned by the mapping function are transformed /// into a parse error. /// #[derive(Debug, Clone, Copy)] pub struct MapRes<P, F, O, E2> { parser: P, func: F, phantom: PhantomData<(O, E2)>, } impl<P, F, I, O, E, O2, E2> Parser<I, O2, E> for MapRes<P, F, O, E2> where P: Parser<I, O, E>, F: FnMut(O) -> Result<O2, E2>, E: FromExternalError<I, E2>, I: Clone, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O2, E> { let (tail, value) = self.parser.parse(input.clone())?; (self.func)(value) .map(move |value| (tail, value)) .map_err(move |err| { NomErr::Error(E::from_external_error(input, NomErrorKind::MapRes, err)) }) } } /// Parser which runs a subparser but doesn't consume any input #[derive(Debug, Clone, Copy)] pub struct Peek<P> { parser: P, } impl<I, O, E, P> Parser<I, O, E> for Peek<P> where P: Parser<I, O, E>, I: Clone, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, O, E> { self.parser .parse(input.clone()) .map(|(_, value)| (input, value)) } } /// Parser which returns failure if the subparser succeeds, and succeeds if the /// subparser fails. #[derive(Debug, Clone, Copy)] pub struct Not<P, O> { parser: P, phantom: PhantomData<O>, } impl<I, O, E, P> Parser<I, (), E> for Not<P, O> where P: Parser<I, O, E>, I: Clone, E: ParseError<I>, { #[inline] fn parse(&mut self, input: I) -> nom::IResult<I, (), E> { match self.parser.parse(input.clone()) { Ok(..) => Err(NomErr::Error(E::from_error_kind(input, NomErrorKind::Not))), Err(NomErr::Error(..)) => Ok((input, ())), Err(err) => Err(err), } } } /// Parser which parses something via [`FromStr`], using a subparser as a /// recognizer for the string to pass to [`from_str`][FromStr::from_str]. #[derive(Debug, Clone, Copy)] pub struct FromStrParser<P, T> { parser: P, phantom: PhantomData<T>, } impl<'a, T, E, P> Parser<&'a str, T, E> for FromStrParser<P, T> where P: Parser<&'a str, &'a str, E>, T: FromStr, E: FromExternalError<&'a str, T::Err>, { #[inline] fn parse(&mut self, input: &'a str) -> nom::IResult<&'a str, T, E> { let (tail, value_str) = self.parser.parse(input)?; match value_str.parse() { Ok(value) => Ok((tail, value)), Err(parse_err) => Err(NomErr::Error(E::from_external_error( input, NomErrorKind::MapRes, parse_err, ))), } } }