Trait MaybeLiteral

Source

pub trait MaybeLiteral {
    // Required method
    fn extend_literal<T: Extend<char>>(
        &self,
        result: &mut T,
    ) -> Result<(), NotLiteral>;

    // Provided method
    fn to_string_if_literal(&self) -> Option<String> { ... }
}

Expand description

Possibly literal syntax element

A syntax element is literal if it is not quoted and does not contain any expansions. Such an element may be considered as a constant string, and is a candidate for a keyword or identifier.

let text = Text(vec![Literal('f'), Literal('o'), Literal('o')]);
let expanded = text.to_string_if_literal().unwrap();
assert_eq!(expanded, "foo");

let backslashed = Text(vec![Backslashed('a')]);
assert_eq!(backslashed.to_string_if_literal(), None);

Required Methods§

Source

fn extend_literal<T: Extend<char>>( &self, result: &mut T, ) -> Result<(), NotLiteral>

Appends the literal representation of self to an extendable object.

If self is literal, the literal representation is appended to result and Ok(()) is returned. Otherwise, Err(NotLiteral) is returned and result may contain some characters that have been appended.