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use peg::RuleResult;
peg::parser!( grammar test() for str {
rule position() -> usize = #{|input, pos| RuleResult::Matched(pos, pos)}
pub rule test1() -> usize = ['a']* p1:position() ['b']* { p1 }
pub rule fail() -> usize = #{|input, pos| RuleResult::Failed}
rule custom_literal(literal: &str) = #{|input, pos| {
let l = literal.len();
if input.len() >= pos + l && &input.as_bytes()[pos..pos + l] == literal.as_bytes() {
RuleResult::Matched(pos + l, ())
} else {
RuleResult::Failed
}
}}
pub rule test2() = custom_literal("foo") "_" custom_literal("bar")
});
fn main() {
assert_eq!(test::test1("aaaabb"), Ok(4));
assert_eq!(test::fail("aaaabb").unwrap_err().location.offset, 0);
assert_eq!(test::test2("foo_bar"), Ok(()));
}
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