Struct charlexer

pub struct charlexer<'t> {
    pub modify: fn(char) -> String,
    /* private fields */
}

This struct is deprecated by charscanner. It is compatible with Lexer and Lextoken, which are also deprecated. This struct requires the legacy-parser installation feature.

Fields

modify: fn(char) -> String

function to modify char returned by nextsym, can be changed. Both charlexer::make and charlexer::new sets this function initially to |x|{x.to_string()}. For example, some characters such as ‘{’ and ‘}’ cannot be used as terminal symbols of a grammar and must be translated into something like “LBRACE” and “RBRACE”

Implementations

impl<'t> charlexer<'t>

pub fn new<'u: 't>(input: &'u str) -> charlexer<'u>

creates a charlexer that emits only non-whitespace chars

pub fn make<'u: 't>(input: &'u str, kws: bool) -> charlexer<'u>

creates a charlexer with the option of keeping whitespace chars if kws=true

Trait Implementations

impl<'t, AT: Default> Lexer<AT> for charlexer<'t>

fn linenum(&self) -> usize

returns current line number starting from 1

fn column(&self) -> usize

returns the index of the current char, starting from 1

fn current_line(&self) -> &str

returns slice of underlying data using std::str::Chars::as_str

fn nextsym(&mut self) -> Option<Lextoken<AT>>

retrieves the next Lextoken, or None at end-of-stream.