| //! Combinators applying their child parser multiple times |
| |
| use crate::error::ErrMode; |
| use crate::error::ErrorKind; |
| use crate::error::ParseError; |
| use crate::stream::Accumulate; |
| use crate::stream::Range; |
| use crate::stream::Stream; |
| use crate::trace::trace; |
| use crate::IResult; |
| use crate::Parser; |
| |
| /// [`Accumulate`] the output of a parser into a container, like `Vec` |
| /// |
| /// This stops before `n` when the parser returns [`ErrMode::Backtrack`]. To instead chain an error up, see |
| /// [`cut_err`][crate::combinator::cut_err]. |
| /// |
| /// # Arguments |
| /// * `m` The minimum number of iterations. |
| /// * `n` The maximum number of iterations. |
| /// * `f` The parser to apply. |
| /// |
| /// To recognize a series of tokens, [`Accumulate`] into a `()` and then [`Parser::recognize`]. |
| /// |
| /// **Warning:** If the parser passed to `repeat` accepts empty inputs |
| /// (like `alpha0` or `digit0`), `repeat` will return an error, |
| /// to prevent going into an infinite loop. |
| /// |
| /// # Example |
| /// |
| /// Zero or more reptitions: |
| /// ```rust |
| /// # #[cfg(feature = "std")] { |
| /// # use winnow::{error::ErrMode, error::ErrorKind, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::repeat; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, Vec<&str>> { |
| /// repeat(0.., "abc").parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("abcabc"), Ok(("", vec!["abc", "abc"]))); |
| /// assert_eq!(parser("abc123"), Ok(("123", vec!["abc"]))); |
| /// assert_eq!(parser("123123"), Ok(("123123", vec![]))); |
| /// assert_eq!(parser(""), Ok(("", vec![]))); |
| /// # } |
| /// ``` |
| /// |
| /// One or more reptitions: |
| /// ```rust |
| /// # #[cfg(feature = "std")] { |
| /// # use winnow::{error::ErrMode, error::{Error, ErrorKind}, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::repeat; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, Vec<&str>> { |
| /// repeat(1.., "abc").parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("abcabc"), Ok(("", vec!["abc", "abc"]))); |
| /// assert_eq!(parser("abc123"), Ok(("123", vec!["abc"]))); |
| /// assert_eq!(parser("123123"), Err(ErrMode::Backtrack(Error::new("123123", ErrorKind::Tag)))); |
| /// assert_eq!(parser(""), Err(ErrMode::Backtrack(Error::new("", ErrorKind::Tag)))); |
| /// # } |
| /// ``` |
| /// |
| /// Fixed number of repeitions: |
| /// ```rust |
| /// # #[cfg(feature = "std")] { |
| /// # use winnow::{error::ErrMode, error::{Error, ErrorKind}, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::repeat; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, Vec<&str>> { |
| /// repeat(2, "abc").parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("abcabc"), Ok(("", vec!["abc", "abc"]))); |
| /// assert_eq!(parser("abc123"), Err(ErrMode::Backtrack(Error::new("123", ErrorKind::Tag)))); |
| /// assert_eq!(parser("123123"), Err(ErrMode::Backtrack(Error::new("123123", ErrorKind::Tag)))); |
| /// assert_eq!(parser(""), Err(ErrMode::Backtrack(Error::new("", ErrorKind::Tag)))); |
| /// assert_eq!(parser("abcabcabc"), Ok(("abc", vec!["abc", "abc"]))); |
| /// # } |
| /// ``` |
| /// |
| /// Arbitrary reptitions: |
| /// ```rust |
| /// # #[cfg(feature = "std")] { |
| /// # use winnow::{error::ErrMode, error::ErrorKind, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::repeat; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, Vec<&str>> { |
| /// repeat(0..=2, "abc").parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("abcabc"), Ok(("", vec!["abc", "abc"]))); |
| /// assert_eq!(parser("abc123"), Ok(("123", vec!["abc"]))); |
| /// assert_eq!(parser("123123"), Ok(("123123", vec![]))); |
| /// assert_eq!(parser(""), Ok(("", vec![]))); |
| /// assert_eq!(parser("abcabcabc"), Ok(("abc", vec!["abc", "abc"]))); |
| /// # } |
| /// ``` |
| #[doc(alias = "many0")] |
| #[doc(alias = "count")] |
| #[doc(alias = "many0_count")] |
| #[doc(alias = "many1")] |
| #[doc(alias = "many1_count")] |
| #[doc(alias = "many_m_n")] |
| #[doc(alias = "repeated")] |
| #[doc(alias = "skip_many")] |
| #[doc(alias = "skip_many1")] |
| #[inline(always)] |
| pub fn repeat<I, O, C, E, F>(range: impl Into<Range>, mut f: F) -> impl Parser<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| F: Parser<I, O, E>, |
| E: ParseError<I>, |
| { |
| let Range { |
| start_inclusive, |
| end_inclusive, |
| } = range.into(); |
| trace("repeat", move |i: I| { |
| match (start_inclusive, end_inclusive) { |
| (0, None) => repeat0_(&mut f, i), |
| (1, None) => repeat1_(&mut f, i), |
| (start, end) if Some(start) == end => repeat_n_(start, &mut f, i), |
| (start, end) => repeat_m_n_(start, end.unwrap_or(usize::MAX), &mut f, i), |
| } |
| }) |
| } |
| |
| /// Deprecated, replaced by [`repeat`] |
| #[deprecated(since = "0.4.6", note = "Replaced with `repeat`")] |
| #[inline(always)] |
| pub fn repeat0<I, O, C, E, F>(f: F) -> impl Parser<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| F: Parser<I, O, E>, |
| E: ParseError<I>, |
| { |
| repeat(0.., f) |
| } |
| |
| fn repeat0_<I, O, C, E, F>(f: &mut F, mut i: I) -> IResult<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| F: Parser<I, O, E>, |
| E: ParseError<I>, |
| { |
| let mut acc = C::initial(None); |
| loop { |
| let len = i.eof_offset(); |
| match f.parse_next(i.clone()) { |
| Err(ErrMode::Backtrack(_)) => return Ok((i, acc)), |
| Err(e) => return Err(e), |
| Ok((i1, o)) => { |
| // infinite loop check: the parser must always consume |
| if i1.eof_offset() == len { |
| return Err(ErrMode::assert(i, "`repeat` parsers must always consume")); |
| } |
| |
| i = i1; |
| acc.accumulate(o); |
| } |
| } |
| } |
| } |
| |
| /// Deprecated, replaced by [`repeat`] |
| #[deprecated(since = "0.4.6", note = "Replaced with `repeat`")] |
| #[inline(always)] |
| pub fn repeat1<I, O, C, E, F>(f: F) -> impl Parser<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| F: Parser<I, O, E>, |
| E: ParseError<I>, |
| { |
| repeat(1.., f) |
| } |
| |
| fn repeat1_<I, O, C, E, F>(f: &mut F, mut i: I) -> IResult<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| F: Parser<I, O, E>, |
| E: ParseError<I>, |
| { |
| match f.parse_next(i.clone()) { |
| Err(e) => Err(e.append(i, ErrorKind::Many)), |
| Ok((i1, o)) => { |
| let mut acc = C::initial(None); |
| acc.accumulate(o); |
| i = i1; |
| |
| loop { |
| let len = i.eof_offset(); |
| match f.parse_next(i.clone()) { |
| Err(ErrMode::Backtrack(_)) => return Ok((i, acc)), |
| Err(e) => return Err(e), |
| Ok((i1, o)) => { |
| // infinite loop check: the parser must always consume |
| if i1.eof_offset() == len { |
| return Err(ErrMode::assert(i, "`repeat` parsers must always consume")); |
| } |
| |
| i = i1; |
| acc.accumulate(o); |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| /// [`Accumulate`] the output of parser `f` into a container, like `Vec`, until the parser `g` |
| /// produces a result. |
| /// |
| /// Returns a tuple of the results of `f` in a `Vec` and the result of `g`. |
| /// |
| /// `f` keeps going so long as `g` produces [`ErrMode::Backtrack`]. To instead chain an error up, see [`cut_err`][crate::combinator::cut_err]. |
| /// |
| /// To recognize a series of tokens, [`Accumulate`] into a `()` and then [`Parser::recognize`]. |
| /// |
| /// # Example |
| /// |
| /// ```rust |
| /// # #[cfg(feature = "std")] { |
| /// # use winnow::{error::ErrMode, error::{Error, ErrorKind}, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::repeat_till0; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, (Vec<&str>, &str)> { |
| /// repeat_till0("abc", "end").parse_next(s) |
| /// }; |
| /// |
| /// assert_eq!(parser("abcabcend"), Ok(("", (vec!["abc", "abc"], "end")))); |
| /// assert_eq!(parser("abc123end"), Err(ErrMode::Backtrack(Error::new("123end", ErrorKind::Tag)))); |
| /// assert_eq!(parser("123123end"), Err(ErrMode::Backtrack(Error::new("123123end", ErrorKind::Tag)))); |
| /// assert_eq!(parser(""), Err(ErrMode::Backtrack(Error::new("", ErrorKind::Tag)))); |
| /// assert_eq!(parser("abcendefg"), Ok(("efg", (vec!["abc"], "end")))); |
| /// # } |
| /// ``` |
| #[doc(alias = "many_till0")] |
| pub fn repeat_till0<I, O, C, P, E, F, G>(mut f: F, mut g: G) -> impl Parser<I, (C, P), E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| F: Parser<I, O, E>, |
| G: Parser<I, P, E>, |
| E: ParseError<I>, |
| { |
| trace("repeat_till0", move |mut i: I| { |
| let mut res = C::initial(None); |
| loop { |
| let len = i.eof_offset(); |
| match g.parse_next(i.clone()) { |
| Ok((i1, o)) => return Ok((i1, (res, o))), |
| Err(ErrMode::Backtrack(_)) => { |
| match f.parse_next(i.clone()) { |
| Err(e) => return Err(e.append(i, ErrorKind::Many)), |
| Ok((i1, o)) => { |
| // infinite loop check: the parser must always consume |
| if i1.eof_offset() == len { |
| return Err(ErrMode::assert( |
| i, |
| "`repeat` parsers must always consume", |
| )); |
| } |
| |
| res.accumulate(o); |
| i = i1; |
| } |
| } |
| } |
| Err(e) => return Err(e), |
| } |
| } |
| }) |
| } |
| |
| /// [`Accumulate`] the output of a parser, interleaed with `sep` |
| /// |
| /// This stops when either parser returns [`ErrMode::Backtrack`]. To instead chain an error up, see |
| /// [`cut_err`][crate::combinator::cut_err]. |
| /// |
| /// # Arguments |
| /// * `parser` Parses the elements of the list. |
| /// * `sep` Parses the separator between list elements. |
| /// |
| /// # Example |
| /// |
| /// ```rust |
| /// # #[cfg(feature = "std")] { |
| /// # use winnow::{error::ErrMode, error::ErrorKind, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::separated0; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, Vec<&str>> { |
| /// separated0("abc", "|").parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("abc|abc|abc"), Ok(("", vec!["abc", "abc", "abc"]))); |
| /// assert_eq!(parser("abc123abc"), Ok(("123abc", vec!["abc"]))); |
| /// assert_eq!(parser("abc|def"), Ok(("|def", vec!["abc"]))); |
| /// assert_eq!(parser(""), Ok(("", vec![]))); |
| /// assert_eq!(parser("def|abc"), Ok(("def|abc", vec![]))); |
| /// # } |
| /// ``` |
| #[doc(alias = "sep_by")] |
| #[doc(alias = "separated_list0")] |
| pub fn separated0<I, O, C, O2, E, P, S>(mut parser: P, mut sep: S) -> impl Parser<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| P: Parser<I, O, E>, |
| S: Parser<I, O2, E>, |
| E: ParseError<I>, |
| { |
| trace("separated0", move |mut i: I| { |
| let mut res = C::initial(None); |
| |
| match parser.parse_next(i.clone()) { |
| Err(ErrMode::Backtrack(_)) => return Ok((i, res)), |
| Err(e) => return Err(e), |
| Ok((i1, o)) => { |
| res.accumulate(o); |
| i = i1; |
| } |
| } |
| |
| loop { |
| let len = i.eof_offset(); |
| match sep.parse_next(i.clone()) { |
| Err(ErrMode::Backtrack(_)) => return Ok((i, res)), |
| Err(e) => return Err(e), |
| Ok((i1, _)) => { |
| // infinite loop check: the parser must always consume |
| if i1.eof_offset() == len { |
| return Err(ErrMode::assert(i, "sep parsers must always consume")); |
| } |
| |
| match parser.parse_next(i1.clone()) { |
| Err(ErrMode::Backtrack(_)) => return Ok((i, res)), |
| Err(e) => return Err(e), |
| Ok((i2, o)) => { |
| res.accumulate(o); |
| i = i2; |
| } |
| } |
| } |
| } |
| } |
| }) |
| } |
| |
| /// [`Accumulate`] the output of a parser, interleaed with `sep` |
| /// |
| /// Fails if the element parser does not produce at least one element.$ |
| /// |
| /// This stops when either parser returns [`ErrMode::Backtrack`]. To instead chain an error up, see |
| /// [`cut_err`][crate::combinator::cut_err]. |
| /// |
| /// # Arguments |
| /// * `sep` Parses the separator between list elements. |
| /// * `f` Parses the elements of the list. |
| /// |
| /// # Example |
| /// |
| /// ```rust |
| /// # #[cfg(feature = "std")] { |
| /// # use winnow::{error::ErrMode, error::{Error, ErrorKind}, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::separated1; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, Vec<&str>> { |
| /// separated1("abc", "|").parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("abc|abc|abc"), Ok(("", vec!["abc", "abc", "abc"]))); |
| /// assert_eq!(parser("abc123abc"), Ok(("123abc", vec!["abc"]))); |
| /// assert_eq!(parser("abc|def"), Ok(("|def", vec!["abc"]))); |
| /// assert_eq!(parser(""), Err(ErrMode::Backtrack(Error::new("", ErrorKind::Tag)))); |
| /// assert_eq!(parser("def|abc"), Err(ErrMode::Backtrack(Error::new("def|abc", ErrorKind::Tag)))); |
| /// # } |
| /// ``` |
| #[doc(alias = "sep_by1")] |
| #[doc(alias = "separated_list1")] |
| pub fn separated1<I, O, C, O2, E, P, S>(mut parser: P, mut sep: S) -> impl Parser<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| P: Parser<I, O, E>, |
| S: Parser<I, O2, E>, |
| E: ParseError<I>, |
| { |
| trace("separated1", move |mut i: I| { |
| let mut res = C::initial(None); |
| |
| // Parse the first element |
| match parser.parse_next(i.clone()) { |
| Err(e) => return Err(e), |
| Ok((i1, o)) => { |
| res.accumulate(o); |
| i = i1; |
| } |
| } |
| |
| loop { |
| let len = i.eof_offset(); |
| match sep.parse_next(i.clone()) { |
| Err(ErrMode::Backtrack(_)) => return Ok((i, res)), |
| Err(e) => return Err(e), |
| Ok((i1, _)) => { |
| // infinite loop check: the parser must always consume |
| if i1.eof_offset() == len { |
| return Err(ErrMode::assert(i, "sep parsers must always consume")); |
| } |
| |
| match parser.parse_next(i1.clone()) { |
| Err(ErrMode::Backtrack(_)) => return Ok((i, res)), |
| Err(e) => return Err(e), |
| Ok((i2, o)) => { |
| res.accumulate(o); |
| i = i2; |
| } |
| } |
| } |
| } |
| } |
| }) |
| } |
| |
| /// Alternates between two parsers, merging the results (left associative) |
| /// |
| /// This stops when either parser returns [`ErrMode::Backtrack`]. To instead chain an error up, see |
| /// [`cut_err`][crate::combinator::cut_err]. |
| /// |
| /// # Example |
| /// |
| /// ```rust |
| /// # use winnow::{error::ErrMode, error::{Error, ErrorKind}, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::separated_foldl1; |
| /// use winnow::ascii::dec_int; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, i32> { |
| /// separated_foldl1(dec_int, "-", |l, _, r| l - r).parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("9-3-5"), Ok(("", 1))); |
| /// assert_eq!(parser(""), Err(ErrMode::Backtrack(Error::new("", ErrorKind::Slice)))); |
| /// assert_eq!(parser("def|abc"), Err(ErrMode::Backtrack(Error::new("def|abc", ErrorKind::Slice)))); |
| /// ``` |
| pub fn separated_foldl1<I, O, O2, E, P, S, Op>( |
| mut parser: P, |
| mut sep: S, |
| op: Op, |
| ) -> impl Parser<I, O, E> |
| where |
| I: Stream, |
| P: Parser<I, O, E>, |
| S: Parser<I, O2, E>, |
| E: ParseError<I>, |
| Op: Fn(O, O2, O) -> O, |
| { |
| trace("separated_foldl1", move |i: I| { |
| let (mut i, mut ol) = parser.parse_next(i)?; |
| |
| loop { |
| let len = i.eof_offset(); |
| match sep.parse_next(i.clone()) { |
| Err(ErrMode::Backtrack(_)) => return Ok((i, ol)), |
| Err(e) => return Err(e), |
| Ok((i1, s)) => { |
| // infinite loop check: the parser must always consume |
| if i1.eof_offset() == len { |
| return Err(ErrMode::assert(i, "`repeat` parsers must always consume")); |
| } |
| |
| match parser.parse_next(i1.clone()) { |
| Err(ErrMode::Backtrack(_)) => return Ok((i, ol)), |
| Err(e) => return Err(e), |
| Ok((i2, or)) => { |
| ol = op(ol, s, or); |
| i = i2; |
| } |
| } |
| } |
| } |
| } |
| }) |
| } |
| |
| /// Alternates between two parsers, merging the results (right associative) |
| /// |
| /// This stops when either parser returns [`ErrMode::Backtrack`]. To instead chain an error up, see |
| /// [`cut_err`][crate::combinator::cut_err]. |
| /// |
| /// # Example |
| /// |
| /// ``` |
| /// # use winnow::{error::ErrMode, error::{Error, ErrorKind}, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::separated_foldr1; |
| /// use winnow::ascii::dec_uint; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, u32> { |
| /// separated_foldr1(dec_uint, "^", |l: u32, _, r: u32| l.pow(r)).parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("2^3^2"), Ok(("", 512))); |
| /// assert_eq!(parser("2"), Ok(("", 2))); |
| /// assert_eq!(parser(""), Err(ErrMode::Backtrack(Error::new("", ErrorKind::Slice)))); |
| /// assert_eq!(parser("def|abc"), Err(ErrMode::Backtrack(Error::new("def|abc", ErrorKind::Slice)))); |
| /// ``` |
| #[cfg(feature = "alloc")] |
| pub fn separated_foldr1<I, O, O2, E, P, S, Op>( |
| mut parser: P, |
| mut sep: S, |
| op: Op, |
| ) -> impl Parser<I, O, E> |
| where |
| I: Stream, |
| P: Parser<I, O, E>, |
| S: Parser<I, O2, E>, |
| E: ParseError<I>, |
| Op: Fn(O, O2, O) -> O, |
| { |
| trace("separated_foldr1", move |i: I| { |
| let (i, ol) = parser.parse_next(i)?; |
| let (i, all): (_, crate::lib::std::vec::Vec<(O2, O)>) = |
| repeat(0.., (sep.by_ref(), parser.by_ref())).parse_next(i)?; |
| if let Some((s, or)) = all |
| .into_iter() |
| .rev() |
| .reduce(|(sr, or), (sl, ol)| (sl, op(ol, sr, or))) |
| { |
| let merged = op(ol, s, or); |
| Ok((i, merged)) |
| } else { |
| Ok((i, ol)) |
| } |
| }) |
| } |
| |
| fn repeat_m_n_<I, O, C, E, F>( |
| min: usize, |
| max: usize, |
| parse: &mut F, |
| mut input: I, |
| ) -> IResult<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| F: Parser<I, O, E>, |
| E: ParseError<I>, |
| { |
| if min > max { |
| return Err(ErrMode::Cut(E::from_error_kind(input, ErrorKind::Many))); |
| } |
| |
| let mut res = C::initial(Some(min)); |
| for count in 0..max { |
| let len = input.eof_offset(); |
| match parse.parse_next(input.clone()) { |
| Ok((tail, value)) => { |
| // infinite loop check: the parser must always consume |
| if tail.eof_offset() == len { |
| return Err(ErrMode::assert( |
| input, |
| "`repeat` parsers must always consume", |
| )); |
| } |
| |
| res.accumulate(value); |
| input = tail; |
| } |
| Err(ErrMode::Backtrack(e)) => { |
| if count < min { |
| return Err(ErrMode::Backtrack(e.append(input, ErrorKind::Many))); |
| } else { |
| return Ok((input, res)); |
| } |
| } |
| Err(e) => { |
| return Err(e); |
| } |
| } |
| } |
| |
| Ok((input, res)) |
| } |
| |
| /// Deprecated, replaced by [`repeat`] |
| #[deprecated(since = "0.4.6", note = "Replaced with `repeat`")] |
| #[inline(always)] |
| pub fn count<I, O, C, E, F>(f: F, count: usize) -> impl Parser<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| F: Parser<I, O, E>, |
| E: ParseError<I>, |
| { |
| repeat(count, f) |
| } |
| |
| fn repeat_n_<I, O, C, E, F>(count: usize, f: &mut F, i: I) -> IResult<I, C, E> |
| where |
| I: Stream, |
| C: Accumulate<O>, |
| F: Parser<I, O, E>, |
| E: ParseError<I>, |
| { |
| let mut input = i.clone(); |
| let mut res = C::initial(Some(count)); |
| |
| for _ in 0..count { |
| let input_ = input.clone(); |
| match f.parse_next(input_) { |
| Ok((i, o)) => { |
| res.accumulate(o); |
| input = i; |
| } |
| Err(e) => { |
| return Err(e.append(i, ErrorKind::Many)); |
| } |
| } |
| } |
| |
| Ok((input, res)) |
| } |
| |
| /// Repeats the embedded parser, filling the given slice with results. |
| /// |
| /// This parser fails if the input runs out before the given slice is full. |
| /// |
| /// # Arguments |
| /// * `f` The parser to apply. |
| /// * `buf` The slice to fill |
| /// |
| /// # Example |
| /// |
| /// ```rust |
| /// # use winnow::{error::ErrMode, error::{Error, ErrorKind}, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::fill; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, [&str; 2]> { |
| /// let mut buf = ["", ""]; |
| /// let (rest, ()) = fill("abc", &mut buf).parse_next(s)?; |
| /// Ok((rest, buf)) |
| /// } |
| /// |
| /// assert_eq!(parser("abcabc"), Ok(("", ["abc", "abc"]))); |
| /// assert_eq!(parser("abc123"), Err(ErrMode::Backtrack(Error::new("123", ErrorKind::Tag)))); |
| /// assert_eq!(parser("123123"), Err(ErrMode::Backtrack(Error::new("123123", ErrorKind::Tag)))); |
| /// assert_eq!(parser(""), Err(ErrMode::Backtrack(Error::new("", ErrorKind::Tag)))); |
| /// assert_eq!(parser("abcabcabc"), Ok(("abc", ["abc", "abc"]))); |
| /// ``` |
| pub fn fill<'a, I, O, E, F>(mut f: F, buf: &'a mut [O]) -> impl Parser<I, (), E> + 'a |
| where |
| I: Stream + 'a, |
| F: Parser<I, O, E> + 'a, |
| E: ParseError<I> + 'a, |
| { |
| trace("fill", move |i: I| { |
| let mut input = i.clone(); |
| |
| for elem in buf.iter_mut() { |
| let input_ = input.clone(); |
| match f.parse_next(input_) { |
| Ok((i, o)) => { |
| *elem = o; |
| input = i; |
| } |
| Err(e) => { |
| return Err(e.append(i, ErrorKind::Many)); |
| } |
| } |
| } |
| |
| Ok((input, ())) |
| }) |
| } |
| |
| /// Repeats the embedded parser `m..=n` times, calling `g` to gather the results |
| /// |
| /// This stops before `n` when the parser returns [`ErrMode::Backtrack`]. To instead chain an error up, see |
| /// [`cut_err`][crate::combinator::cut_err]. |
| /// |
| /// # Arguments |
| /// * `m` The minimum number of iterations. |
| /// * `n` The maximum number of iterations. |
| /// * `f` The parser to apply. |
| /// * `init` A function returning the initial value. |
| /// * `g` The function that combines a result of `f` with |
| /// the current accumulator. |
| /// |
| /// **Warning:** If the parser passed to `fold_repeat` accepts empty inputs |
| /// (like `alpha0` or `digit0`), `fold_repeat` will return an error, |
| /// to prevent going into an infinite loop. |
| /// |
| /// # Example |
| /// |
| /// Zero or more repetitions: |
| /// ```rust |
| /// # use winnow::{error::ErrMode, error::ErrorKind, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::fold_repeat; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, Vec<&str>> { |
| /// fold_repeat( |
| /// 0.., |
| /// "abc", |
| /// Vec::new, |
| /// |mut acc: Vec<_>, item| { |
| /// acc.push(item); |
| /// acc |
| /// } |
| /// ).parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("abcabc"), Ok(("", vec!["abc", "abc"]))); |
| /// assert_eq!(parser("abc123"), Ok(("123", vec!["abc"]))); |
| /// assert_eq!(parser("123123"), Ok(("123123", vec![]))); |
| /// assert_eq!(parser(""), Ok(("", vec![]))); |
| /// ``` |
| /// |
| /// One or more repetitions: |
| /// ```rust |
| /// # use winnow::{error::ErrMode, error::{Error, ErrorKind}, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::fold_repeat; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, Vec<&str>> { |
| /// fold_repeat( |
| /// 1.., |
| /// "abc", |
| /// Vec::new, |
| /// |mut acc: Vec<_>, item| { |
| /// acc.push(item); |
| /// acc |
| /// } |
| /// ).parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("abcabc"), Ok(("", vec!["abc", "abc"]))); |
| /// assert_eq!(parser("abc123"), Ok(("123", vec!["abc"]))); |
| /// assert_eq!(parser("123123"), Err(ErrMode::Backtrack(Error::new("123123", ErrorKind::Many)))); |
| /// assert_eq!(parser(""), Err(ErrMode::Backtrack(Error::new("", ErrorKind::Many)))); |
| /// ``` |
| /// |
| /// Arbitrary number of repetitions: |
| /// ```rust |
| /// # use winnow::{error::ErrMode, error::ErrorKind, error::Needed}; |
| /// # use winnow::prelude::*; |
| /// use winnow::combinator::fold_repeat; |
| /// use winnow::token::tag; |
| /// |
| /// fn parser(s: &str) -> IResult<&str, Vec<&str>> { |
| /// fold_repeat( |
| /// 0..=2, |
| /// "abc", |
| /// Vec::new, |
| /// |mut acc: Vec<_>, item| { |
| /// acc.push(item); |
| /// acc |
| /// } |
| /// ).parse_next(s) |
| /// } |
| /// |
| /// assert_eq!(parser("abcabc"), Ok(("", vec!["abc", "abc"]))); |
| /// assert_eq!(parser("abc123"), Ok(("123", vec!["abc"]))); |
| /// assert_eq!(parser("123123"), Ok(("123123", vec![]))); |
| /// assert_eq!(parser(""), Ok(("", vec![]))); |
| /// assert_eq!(parser("abcabcabc"), Ok(("abc", vec!["abc", "abc"]))); |
| /// ``` |
| #[doc(alias = "fold_many0")] |
| #[doc(alias = "fold_many1")] |
| #[doc(alias = "fold_many_m_n")] |
| #[inline(always)] |
| pub fn fold_repeat<I, O, E, F, G, H, R>( |
| range: impl Into<Range>, |
| mut f: F, |
| mut init: H, |
| mut g: G, |
| ) -> impl Parser<I, R, E> |
| where |
| I: Stream, |
| F: Parser<I, O, E>, |
| G: FnMut(R, O) -> R, |
| H: FnMut() -> R, |
| E: ParseError<I>, |
| { |
| let Range { |
| start_inclusive, |
| end_inclusive, |
| } = range.into(); |
| trace("fold_repeat", move |i: I| { |
| match (start_inclusive, end_inclusive) { |
| (0, None) => fold_repeat0_(&mut f, &mut init, &mut g, i), |
| (1, None) => fold_repeat1_(&mut f, &mut init, &mut g, i), |
| (start, end) => fold_repeat_m_n_( |
| start, |
| end.unwrap_or(usize::MAX), |
| &mut f, |
| &mut init, |
| &mut g, |
| i, |
| ), |
| } |
| }) |
| } |
| |
| /// Deprecated, replaced by [`fold_repeat`] |
| #[deprecated(since = "0.4.6", note = "Replaced with `fold_repeat`")] |
| #[inline(always)] |
| pub fn fold_repeat0<I, O, E, F, G, H, R>(mut f: F, mut init: H, mut g: G) -> impl Parser<I, R, E> |
| where |
| I: Stream, |
| F: Parser<I, O, E>, |
| G: FnMut(R, O) -> R, |
| H: FnMut() -> R, |
| E: ParseError<I>, |
| { |
| trace("fold_repeat0", move |i: I| { |
| fold_repeat0_(&mut f, &mut init, &mut g, i) |
| }) |
| } |
| |
| fn fold_repeat0_<I, O, E, F, G, H, R>(f: &mut F, init: &mut H, g: &mut G, i: I) -> IResult<I, R, E> |
| where |
| I: Stream, |
| F: Parser<I, O, E>, |
| G: FnMut(R, O) -> R, |
| H: FnMut() -> R, |
| E: ParseError<I>, |
| { |
| let mut res = init(); |
| let mut input = i; |
| |
| loop { |
| let i_ = input.clone(); |
| let len = input.eof_offset(); |
| match f.parse_next(i_) { |
| Ok((i, o)) => { |
| // infinite loop check: the parser must always consume |
| if i.eof_offset() == len { |
| return Err(ErrMode::assert(i, "`repeat` parsers must always consume")); |
| } |
| |
| res = g(res, o); |
| input = i; |
| } |
| Err(ErrMode::Backtrack(_)) => { |
| return Ok((input, res)); |
| } |
| Err(e) => { |
| return Err(e); |
| } |
| } |
| } |
| } |
| |
| /// Deprecated, replaced by [`fold_repeat`] |
| #[deprecated(since = "0.4.6", note = "Replaced with `fold_repeat`")] |
| #[inline(always)] |
| pub fn fold_repeat1<I, O, E, F, G, H, R>(mut f: F, mut init: H, mut g: G) -> impl Parser<I, R, E> |
| where |
| I: Stream, |
| F: Parser<I, O, E>, |
| G: FnMut(R, O) -> R, |
| H: FnMut() -> R, |
| E: ParseError<I>, |
| { |
| trace("fold_repeat1", move |i: I| { |
| fold_repeat1_(&mut f, &mut init, &mut g, i) |
| }) |
| } |
| |
| fn fold_repeat1_<I, O, E, F, G, H, R>(f: &mut F, init: &mut H, g: &mut G, i: I) -> IResult<I, R, E> |
| where |
| I: Stream, |
| F: Parser<I, O, E>, |
| G: FnMut(R, O) -> R, |
| H: FnMut() -> R, |
| E: ParseError<I>, |
| { |
| let _i = i.clone(); |
| let init = init(); |
| match f.parse_next(_i) { |
| Err(ErrMode::Backtrack(_)) => Err(ErrMode::from_error_kind(i, ErrorKind::Many)), |
| Err(e) => Err(e), |
| Ok((i1, o1)) => { |
| let mut acc = g(init, o1); |
| let mut input = i1; |
| |
| loop { |
| let _input = input.clone(); |
| let len = input.eof_offset(); |
| match f.parse_next(_input) { |
| Err(ErrMode::Backtrack(_)) => { |
| break; |
| } |
| Err(e) => return Err(e), |
| Ok((i, o)) => { |
| // infinite loop check: the parser must always consume |
| if i.eof_offset() == len { |
| return Err(ErrMode::assert(i, "`repeat` parsers must always consume")); |
| } |
| |
| acc = g(acc, o); |
| input = i; |
| } |
| } |
| } |
| |
| Ok((input, acc)) |
| } |
| } |
| } |
| |
| fn fold_repeat_m_n_<I, O, E, F, G, H, R>( |
| min: usize, |
| max: usize, |
| parse: &mut F, |
| init: &mut H, |
| fold: &mut G, |
| mut input: I, |
| ) -> IResult<I, R, E> |
| where |
| I: Stream, |
| F: Parser<I, O, E>, |
| G: FnMut(R, O) -> R, |
| H: FnMut() -> R, |
| E: ParseError<I>, |
| { |
| if min > max { |
| return Err(ErrMode::Cut(E::from_error_kind(input, ErrorKind::Many))); |
| } |
| |
| let mut acc = init(); |
| for count in 0..max { |
| let len = input.eof_offset(); |
| match parse.parse_next(input.clone()) { |
| Ok((tail, value)) => { |
| // infinite loop check: the parser must always consume |
| if tail.eof_offset() == len { |
| return Err(ErrMode::assert( |
| input, |
| "`repeat` parsers must always consume", |
| )); |
| } |
| |
| acc = fold(acc, value); |
| input = tail; |
| } |
| //FInputXMError: handle failure properly |
| Err(ErrMode::Backtrack(err)) => { |
| if count < min { |
| return Err(ErrMode::Backtrack(err.append(input, ErrorKind::Many))); |
| } else { |
| break; |
| } |
| } |
| Err(e) => return Err(e), |
| } |
| } |
| |
| Ok((input, acc)) |
| } |