mirror of https://github.com/rust-lang/rust
29 lines
640 B
Rust
29 lines
640 B
Rust
//@ run-pass
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// Regression test for issue #25436: permit token-trees to be followed
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// by sequences, enabling more general parsing.
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use self::Join::*;
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#[derive(Debug)]
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#[allow(dead_code)]
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enum Join<A,B> {
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Keep(A,B),
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Skip(A,B),
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}
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macro_rules! parse_list {
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( < $a:expr; > $($b:tt)* ) => { Keep(parse_item!($a),parse_list!($($b)*)) };
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( $a:tt $($b:tt)* ) => { Skip(parse_item!($a), parse_list!($($b)*)) };
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( ) => { () };
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}
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macro_rules! parse_item {
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( $x:expr ) => { $x }
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}
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fn main() {
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let list = parse_list!(<1;> 2 <3;> 4);
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assert_eq!("Keep(1, Skip(2, Keep(3, Skip(4, ()))))",
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format!("{:?}", list));
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}
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