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|
//@ run-pass
macro_rules! mtester {
($l:literal) => {
&format!("macro caught literal: {}", $l)
};
($e:expr) => {
&format!("macro caught expr: {}", $e)
};
}
macro_rules! two_negative_literals {
($l1:literal $l2:literal) => {
&format!("macro caught literals: {}, {}", $l1, $l2)
};
}
macro_rules! only_expr {
($e:expr) => {
&format!("macro caught expr: {}", $e)
};
}
#[allow(unused_macro_rules)]
macro_rules! mtester_dbg {
($l:literal) => {
&format!("macro caught literal: {:?}", $l)
};
($e:expr) => {
&format!("macro caught expr: {:?}", $e)
};
}
macro_rules! catch_range {
($s:literal ..= $e:literal) => {
&format!("macro caught literal: {} ..= {}", $s, $e)
};
(($s:expr) ..= ($e:expr)) => { // Must use ')' before '..='
&format!("macro caught expr: {} ..= {}", $s, $e)
};
}
macro_rules! pat_match {
($s:literal ..= $e:literal) => {
match 3 {
$s ..= $e => "literal, in range",
_ => "literal, other",
}
};
($s:pat) => {
match 3 {
$s => "pat, single",
_ => "pat, other",
}
};
}
macro_rules! match_attr {
(#[$attr:meta] $e:literal) => {
"attr matched literal"
};
(#[$attr:meta] $e:expr) => {
"attr matched expr"
};
}
macro_rules! match_produced_attr {
($lit: literal) => {
// Struct with doc comment passed via $literal
#[doc = $lit]
struct LiteralProduced;
};
($expr: expr) => {
struct ExprProduced;
};
}
macro_rules! test_user {
($s:literal, $e:literal) => {
{
let mut v = Vec::new();
for i in $s .. $e {
v.push(i);
}
"literal"
}
};
($s:expr, $e: expr) => {
{
let mut v = Vec::new();
for i in $s .. $e {
v.push(i);
}
"expr"
}
};
}
pub fn main() {
// Cases where 'literal' catches
assert_eq!(mtester!("str"), "macro caught literal: str");
assert_eq!(mtester!(2), "macro caught literal: 2");
assert_eq!(mtester!(2.2), "macro caught literal: 2.2");
assert_eq!(mtester!(1u32), "macro caught literal: 1");
assert_eq!(mtester!(0x32), "macro caught literal: 50");
assert_eq!(mtester!('c'), "macro caught literal: c");
assert_eq!(mtester!(-1.2), "macro caught literal: -1.2");
assert_eq!(two_negative_literals!(-2 -3), "macro caught literals: -2, -3");
assert_eq!(catch_range!(2 ..= 3), "macro caught literal: 2 ..= 3");
assert_eq!(match_attr!(#[attr] 1), "attr matched literal");
assert_eq!(test_user!(10, 20), "literal");
assert_eq!(mtester!(false), "macro caught literal: false");
assert_eq!(mtester!(true), "macro caught literal: true");
match_produced_attr!("a");
let _a = LiteralProduced;
assert_eq!(pat_match!(1 ..= 3), "literal, in range");
assert_eq!(pat_match!(4 ..= 6), "literal, other");
// Cases where 'expr' catches
assert_eq!(mtester!((-1.2)), "macro caught expr: -1.2");
assert_eq!(only_expr!(-1.2), "macro caught expr: -1.2");
assert_eq!(mtester!((1 + 3)), "macro caught expr: 4");
assert_eq!(mtester_dbg!(()), "macro caught expr: ()");
assert_eq!(catch_range!((1 + 1) ..= (2 + 2)), "macro caught expr: 2 ..= 4");
assert_eq!(match_attr!(#[attr] (1 + 2)), "attr matched expr");
assert_eq!(test_user!(10, (20 + 2)), "expr");
match_produced_attr!((3 + 2));
let _b = ExprProduced;
// Cases where 'pat' matched
assert_eq!(pat_match!(3), "pat, single");
assert_eq!(pat_match!(6), "pat, other");
}
|
