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//@ run-pass
#![allow(dead_code, non_camel_case_types, non_upper_case_globals, unused_variables)]
#![feature(macro_metavar_expr_concat)]
macro_rules! create_things {
($lhs:ident) => {
struct ${concat($lhs, _separated_idents_in_a_struct)} {
foo: i32,
${concat($lhs, _separated_idents_in_a_field)}: i32,
}
mod ${concat($lhs, _separated_idents_in_a_module)} {
pub const FOO: () = ();
}
fn ${concat($lhs, _separated_idents_in_a_fn)}() {}
};
}
macro_rules! many_idents {
($a:ident, $c:ident) => {
const ${concat($a, B, $c, D)}: i32 = 1;
};
}
macro_rules! valid_tts {
($_0:tt, $_1:tt) => {
const ${concat($_0, $_1)}: i32 = 1;
}
}
macro_rules! without_dollar_sign_is_an_ident {
($ident:ident) => {
const ${concat(VAR, ident)}: i32 = 1;
const ${concat(VAR, $ident)}: i32 = 2;
};
}
macro_rules! combinations {
($ident:ident, $literal:literal, $tt_ident:tt, $tt_literal:tt) => {{
// tt ident
let ${concat($tt_ident, b)} = ();
let ${concat($tt_ident, _b)} = ();
let ${concat($tt_ident, "b")} = ();
let ${concat($tt_ident, $tt_ident)} = ();
let ${concat($tt_ident, $tt_literal)} = ();
let ${concat($tt_ident, $ident)} = ();
let ${concat($tt_ident, $literal)} = ();
// tt literal
let ${concat($tt_literal, b)} = ();
let ${concat($tt_literal, _b)} = ();
let ${concat($tt_literal, "b")} = ();
let ${concat($tt_literal, $tt_ident)} = ();
let ${concat($tt_literal, $tt_literal)} = ();
let ${concat($tt_literal, $ident)} = ();
let ${concat($tt_literal, $literal)} = ();
// ident (adhoc)
let ${concat(_b, b)} = ();
let ${concat(_b, _b)} = ();
let ${concat(_b, "b")} = ();
let ${concat(_b, $tt_ident)} = ();
let ${concat(_b, $tt_literal)} = ();
let ${concat(_b, $ident)} = ();
let ${concat(_b, $literal)} = ();
// ident (param)
let ${concat($ident, b)} = ();
let ${concat($ident, _b)} = ();
let ${concat($ident, "b")} = ();
let ${concat($ident, $tt_ident)} = ();
let ${concat($ident, $tt_literal)} = ();
let ${concat($ident, $ident)} = ();
let ${concat($ident, $literal)} = ();
// literal (adhoc)
let ${concat("a", b)} = ();
let ${concat("a", _b)} = ();
let ${concat("a", "b")} = ();
let ${concat("a", $tt_ident)} = ();
let ${concat("a", $tt_literal)} = ();
let ${concat("a", $ident)} = ();
let ${concat("a", $literal)} = ();
// literal (param)
let ${concat($literal, b)} = ();
let ${concat($literal, _b)} = ();
let ${concat($literal, "b")} = ();
let ${concat($literal, $tt_ident)} = ();
let ${concat($literal, $tt_literal)} = ();
let ${concat($literal, $ident)} = ();
let ${concat($literal, $literal)} = ();
}};
}
fn main() {
create_things!(behold);
behold_separated_idents_in_a_fn();
let _ = behold_separated_idents_in_a_module::FOO;
let _ = behold_separated_idents_in_a_struct {
foo: 1,
behold_separated_idents_in_a_field: 2,
};
many_idents!(A, C);
assert_eq!(ABCD, 1);
valid_tts!(X, YZ);
assert_eq!(XYZ, 1);
without_dollar_sign_is_an_ident!(_123);
assert_eq!(VARident, 1);
assert_eq!(VAR_123, 2);
combinations!(_hello, "a", b, "b");
}
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