Enum ParseResult

pub enum ParseResult<'a, TokenKind, T, E> {
    Match {
        value: T,
        remaining: TokenStream<'a, TokenKind>,
    },
    NoMatch,
    Err(E),
}

The result of running a parser

Variants

Match

The input matched the parser pattern.

Fields

value: T

The value produced by the parser

remaining: TokenStream<'a, TokenKind>

The remaining token stream

NoMatch

The input did not match the parser pattern.

Err(E)

The input matched the parser pattern but was malformed or invalid.

Implementations

impl<'a, TokenKind, T, E> ParseResult<'a, TokenKind, T, E>

pub fn map<U>(self, f: impl FnOnce(T) -> U) -> ParseResult<'a, TokenKind, U, E>

Maps a ParseResult<'a, TokenKind, T, E> to ParseResult<'a, TokenKind, U, E> by applying a function to a contained ParseResult::Match value, leaving an ParseResult::NoMatch and ParseResult::Err value untouched.

pub fn map_err<F>( self, f: impl FnOnce(E) -> F, ) -> ParseResult<'a, TokenKind, T, F>

Maps a ParseResult<'a, TokenKind, T, E> to ParseResult<'a, TokenKind, T, F> by applying a function to a contained ParseResult::Err value, leaving an ParseResult::Match and ParseResult::NoMatch value untouched.

Trait Implementations

impl<'a, TokenKind, T, E> FromResidual for ParseResult<'a, TokenKind, T, E>

fn from_residual(residual: <Self as Try>::Residual) -> Self

🔬This is a nightly-only experimental API. (try_trait_v2)

Constructs the type from a compatible Residual type.

impl<'a, TokenKind, T, E> Try for ParseResult<'a, TokenKind, T, E>

type Output = (T, TokenStream<'a, TokenKind>)

🔬This is a nightly-only experimental API. (try_trait_v2)

The type of the value produced by ? when not short-circuiting.

type Residual = ParseResult<'a, TokenKind, Infallible, E>

🔬This is a nightly-only experimental API. (try_trait_v2)

The type of the value passed to FromResidual::from_residual as part of ? when short-circuiting.

fn from_output((value, remaining): Self::Output) -> Self

🔬This is a nightly-only experimental API. (try_trait_v2)

Constructs the type from its Output type.

fn branch(self) -> ControlFlow<Self::Residual, Self::Output>

🔬This is a nightly-only experimental API. (try_trait_v2)

Used in ? to decide whether the operator should produce a value (because this returned ControlFlow::Continue) or propagate a value back to the caller (because this returned ControlFlow::Break).