Struct wast::parser::Cursor

pub struct Cursor<'a> { /* private fields */ }

An immutable cursor into a list of tokens.

This cursor cannot be mutated but can be used to parse more tokens in a list of tokens. Cursors are created from the Parser::step method. This is a very low-level parsing structure and you likely won’t use it much.

Implementations

impl<'a> Cursor<'a>

pub fn cur_span(&self) -> Span

Returns the span of the next Token token.

Does not take into account whitespace or comments.

pub fn error(&self, msg: impl Display) -> Error

Same as Parser::error, but works with the current token in this Cursor instead.

pub fn peek_lparen(self) -> Result<bool>

Tests whether the next token is an lparen

pub fn peek_rparen(self) -> Result<bool>

Tests whether the next token is an rparen

pub fn peek_id(self) -> Result<bool>

Tests whether the next token is an id

pub fn peek_reserved(self) -> Result<bool>

Tests whether the next token is reserved

pub fn peek_keyword(self) -> Result<bool>

Tests whether the next token is a keyword

pub fn peek_integer(self) -> Result<bool>

Tests whether the next token is an integer

pub fn peek_float(self) -> Result<bool>

Tests whether the next token is a float

pub fn peek_string(self) -> Result<bool>

Tests whether the next token is a string

pub fn lparen(self) -> Result<Option<Self>>

Attempts to advance this cursor if the current token is a (.

If the current token is (, returns a new Cursor pointing at the rest of the tokens in the stream. Otherwise returns None.

This function will automatically skip over any comments, whitespace, or unknown annotations.

pub fn rparen(self) -> Result<Option<Self>>

Attempts to advance this cursor if the current token is a ).

If the current token is ), returns a new Cursor pointing at the rest of the tokens in the stream. Otherwise returns None.

This function will automatically skip over any comments, whitespace, or unknown annotations.

pub fn id(self) -> Result<Option<(&'a str, Self)>>

Attempts to advance this cursor if the current token is a Token::Id

If the current token is Id, returns the identifier minus the leading $ character as well as a new Cursor pointing at the rest of the tokens in the stream. Otherwise returns None.

This function will automatically skip over any comments, whitespace, or unknown annotations.

pub fn keyword(self) -> Result<Option<(&'a str, Self)>>

Attempts to advance this cursor if the current token is a Token::Keyword

If the current token is Keyword, returns the keyword as well as a new Cursor pointing at the rest of the tokens in the stream. Otherwise returns None.

This function will automatically skip over any comments, whitespace, or unknown annotations.

pub fn annotation(self) -> Result<Option<(&'a str, Self)>>

Attempts to advance this cursor if the current token is a Token::Annotation

If the current token is Annotation, returns the annotation token as well as a new Cursor pointing at the rest of the tokens in the stream. Otherwise returns None.

This function will automatically skip over any comments, whitespace, or unknown annotations.

pub fn reserved(self) -> Result<Option<(&'a str, Self)>>

Attempts to advance this cursor if the current token is a Token::Reserved

If the current token is Reserved, returns the reserved token as well as a new Cursor pointing at the rest of the tokens in the stream. Otherwise returns None.

This function will automatically skip over any comments, whitespace, or unknown annotations.

pub fn integer(self) -> Result<Option<(Integer<'a>, Self)>>

Attempts to advance this cursor if the current token is a Token::Integer

If the current token is Integer, returns the integer as well as a new Cursor pointing at the rest of the tokens in the stream. Otherwise returns None.

This function will automatically skip over any comments, whitespace, or unknown annotations.

pub fn float(self) -> Result<Option<(Float<'a>, Self)>>

Attempts to advance this cursor if the current token is a Token::Float

If the current token is Float, returns the float as well as a new Cursor pointing at the rest of the tokens in the stream. Otherwise returns None.

This function will automatically skip over any comments, whitespace, or unknown annotations.

pub fn string(self) -> Result<Option<(&'a [u8], Self)>>

Attempts to advance this cursor if the current token is a Token::String

If the current token is String, returns the byte value of the string as well as a new Cursor pointing at the rest of the tokens in the stream. Otherwise returns None.

This function will automatically skip over any comments, whitespace, or unknown annotations.

pub fn comment(self) -> Result<Option<(&'a str, Self)>>

Attempts to advance this cursor if the current token is a Token::LineComment or a Token::BlockComment

This function will only skip whitespace, no other tokens.

Trait Implementations

impl<'a> Clone for Cursor<'a>

fn clone(&self) -> Cursor<'a>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<'a> Copy for Cursor<'a>