Struct TokenParser 

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

Helper for the composition expression parser: a cursor over the text that consumes tokens from its start.

TokenParser::position and TokenParser::length count UTF-16 code units, the unit of the reference implementation.

Implementations

impl<'a> TokenParser<'a>

pub fn new(s: &'a str) -> Self

Creates a parser over the given text.

pub fn position(&self) -> i32

The number of UTF-16 code units consumed so far.

pub fn skip_whitespace(&mut self)

pub fn next_is_whitespace(&self) -> bool

pub fn try_consume(&mut self, c: char) -> bool

Consumes the given character if it is next (after white space).

pub fn try_consume_str(&mut self, s: &str) -> bool

Consumes the given text if it is next (after white space).

pub fn try_consume_any(&mut self, chars: &str) -> Option<char>

Consumes whichever of the given characters is next (after white space).

pub fn try_parse_keyword(&mut self, keyword: &str) -> bool

Consumes the given keyword if it is next (after white space) and is not followed by a letter or a digit.

pub fn try_parse_keyword_lower_case( &mut self, keyword_in_lower_case: &str, ) -> bool

Like TokenParser::try_parse_keyword, ignoring the case of the text; the keyword must be given in lower case.

pub fn advance(&mut self, c: i32)

Consumes c UTF-16 code units.

pub fn length(&self) -> i32

The number of UTF-16 code units left.

pub fn try_parse_identifier_with( &mut self, extra_valid_chars: &str, ) -> Option<&'a str>

Consumes an identifier: an ASCII letter followed by ASCII letters, digits and any of the extra valid characters.

pub fn try_parse_identifier(&mut self) -> Option<&'a str>

Consumes an identifier: an ASCII letter followed by ASCII letters and digits.

pub fn try_parse_call(&mut self) -> Option<&'a str>

Consumes a function name (an identifier that may contain dots) together with the opening parenthesis that follows it. Nothing is consumed when the name is not followed by a parenthesis.

pub fn try_parse_float(&mut self) -> Option<f32>

Consumes a single-precision number.

pub fn try_parse_double(&mut self) -> Option<f64>

Consumes a double-precision number.

pub fn is_eof_with_whitespace(&mut self) -> bool

Whether only white space is left (which is consumed).

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

The text that has not been consumed yet.

Trait Implementations

impl<'a> Clone for TokenParser<'a>

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Copy for TokenParser<'a>

impl<'a> Debug for TokenParser<'a>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for TokenParser<'_>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.