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38df15805b
When operating on expressions, `cfg_select!` can now handle expressions without braces. (It still requires braces for other things, such as items.) Expand the test coverage and documentation accordingly.
63 lines
1.1 KiB
Rust
63 lines
1.1 KiB
Rust
#![feature(cfg_select)]
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#![crate_type = "lib"]
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fn print() {
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println!(cfg_select! {
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unix => { "unix" }
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_ => { "not unix" }
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});
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}
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fn print_2() {
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println!(cfg_select! {
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unix => "unix",
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_ => "not unix",
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});
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}
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fn arm_rhs_expr_1() -> i32 {
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cfg_select! {
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true => 1
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}
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}
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fn arm_rhs_expr_2() -> i32 {
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cfg_select! {
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true => 1,
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false => 2
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}
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}
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fn arm_rhs_expr_3() -> i32 {
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cfg_select! {
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true => 1,
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false => 2,
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true => { 42 }
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false => -1 as i32,
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true => 2 + 2,
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false => "",
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true => if true { 42 } else { 84 }
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false => if true { 42 } else { 84 },
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true => return 42,
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false => loop {}
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true => (1, 2),
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false => (1, 2,),
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true => todo!(),
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false => println!("hello"),
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}
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}
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cfg_select! {
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_ => {}
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true => {}
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//~^ WARN unreachable predicate
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}
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cfg_select! {
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//~^ ERROR none of the predicates in this `cfg_select` evaluated to true
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false => {}
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}
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cfg_select! {}
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//~^ ERROR none of the predicates in this `cfg_select` evaluated to true
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