Struct Cursor

pub struct Cursor<'a> {
    len_remaining: usize,
    chars: Chars<'a>,
    prev: char,
}

Peekable iterator over a char sequence.

Next characters can be peeked via first method, and position can be shifted forward via bump method.

Fields

len_remaining: usize

chars: Chars<'a>

Iterator over chars. Slightly faster than a &str.

prev: char

Implementations

impl<'a> Cursor<'a>

pub fn new(input: &'a str) -> Cursor<'a>

pub fn as_str(&self) -> &'a str

pub(crate) fn prev(&self) -> char

Returns the last eaten symbol (or '\0' in release builds). (For debug assertions only.)

pub fn first(&self) -> char

Peeks the next symbol from the input stream without consuming it. If requested position doesn’t exist, EOF_CHAR is returned. However, getting EOF_CHAR doesn’t always mean actual end of file, it should be checked with is_eof method.

pub(crate) fn second(&self) -> char

Peeks the second symbol from the input stream without consuming it.

pub fn third(&self) -> char

Peeks the third symbol from the input stream without consuming it.

pub(crate) fn is_eof(&self) -> bool

Checks if there is nothing more to consume.

pub(crate) fn pos_within_token(&self) -> u32

Returns amount of already consumed symbols.

pub(crate) fn reset_pos_within_token(&mut self)

Resets the number of bytes consumed to 0.

pub(crate) fn bump(&mut self) -> Option<char>

Moves to the next character.

pub(crate) fn eat_while(&mut self, predicate: impl FnMut(char) -> bool)

Eats symbols while predicate returns true or until the end of file is reached.

impl Cursor<'_>

pub fn advance_token(&mut self) -> Token

Parses a token from the input string.

pub(crate) fn line_comment(&mut self) -> TokenKind

pub(crate) fn block_comment(&mut self) -> TokenKind

pub(crate) fn whitespace(&mut self) -> TokenKind

pub(crate) fn raw_ident(&mut self) -> TokenKind

pub(crate) fn ident_or_unknown_prefix(&mut self) -> TokenKind

pub(crate) fn invalid_ident(&mut self) -> TokenKind

pub(crate) fn c_or_byte_string( &mut self, mk_kind: impl FnOnce(bool) -> LiteralKind, mk_kind_raw: impl FnOnce(Option<u8>) -> LiteralKind, single_quoted: Option<fn(_: bool) -> LiteralKind>, ) -> TokenKind

pub(crate) fn number(&mut self, first_digit: char) -> LiteralKind

pub(crate) fn lifetime_or_char(&mut self) -> TokenKind

pub(crate) fn single_quoted_string(&mut self) -> bool

pub(crate) fn double_quoted_string(&mut self) -> bool

Eats double-quoted string and returns true if string is terminated.

pub fn guarded_double_quoted_string(&mut self) -> Option<GuardedStr>

Attempt to lex for a guarded string literal.

Used by rustc_parse::lexer to lex for guarded strings conditionally based on edition.

Note: this will not reset the Cursor when a guarded string is not found. It is the caller’s responsibility to do so.

pub(crate) fn raw_double_quoted_string( &mut self, prefix_len: u32, ) -> Result<u8, RawStrError>

Eats the double-quoted string and returns n_hashes and an error if encountered.

pub(crate) fn raw_string_unvalidated( &mut self, prefix_len: u32, ) -> Result<u32, RawStrError>

pub(crate) fn eat_decimal_digits(&mut self) -> bool

pub(crate) fn eat_hexadecimal_digits(&mut self) -> bool

pub(crate) fn eat_float_exponent(&mut self) -> bool

Eats the float exponent. Returns true if at least one digit was met, and returns false otherwise.

pub(crate) fn eat_literal_suffix(&mut self)

pub(crate) fn eat_identifier(&mut self)

Layout

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 32 bytes