49 lines
833 B
Markdown
49 lines
833 B
Markdown
|
# &'static and T: 'static
|
||
|
|
|
||
|
|
```rust,editable
|
||
|
|
use std::fmt::Display;
|
||
|
|
|
||
|
|
fn main() {
|
||
|
|
let mut string = "First".to_owned();
|
||
|
|
|
||
|
|
string.push_str(string.to_uppercase().as_str());
|
||
|
|
print_a(&string);
|
||
|
|
print_b(&string);
|
||
|
|
print_c(&string); // Compilation error
|
||
|
|
print_d(&string); // Compilation error
|
||
|
|
print_e(&string);
|
||
|
|
print_f(&string);
|
||
|
|
print_g(&string); // Compilation error
|
||
|
|
}
|
||
|
|
|
||
|
|
fn print_a<T: Display + 'static>(t: &T) {
|
||
|
|
println!("{}", t);
|
||
|
|
}
|
||
|
|
|
||
|
|
fn print_b<T>(t: &T)
|
||
|
|
where
|
||
|
|
T: Display + 'static,
|
||
|
|
{
|
||
|
|
println!("{}", t);
|
||
|
|
}
|
||
|
|
|
||
|
|
fn print_c(t: &'static dyn Display) {
|
||
|
|
println!("{}", t)
|
||
|
|
}
|
||
|
|
|
||
|
|
fn print_d(t: &'static impl Display) {
|
||
|
|
println!("{}", t)
|
||
|
|
}
|
||
|
|
|
||
|
|
fn print_e(t: &(dyn Display + 'static)) {
|
||
|
|
println!("{}", t)
|
||
|
|
}
|
||
|
|
|
||
|
|
fn print_f(t: &(impl Display + 'static)) {
|
||
|
|
println!("{}", t)
|
||
|
|
}
|
||
|
|
|
||
|
|
fn print_g(t: &'static String) {
|
||
|
|
println!("{}", t);
|
||
|
|
}
|
||
|
|
```
|