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pub fn will_be_called() -> &'static str {
let val = "called";
println!("{}", val);
val
}
pub fn will_not_be_called() -> bool {
println!("should not have been called");
false
}
pub fn print<T>(left: &str, value: T, right: &str)
where
T: std::fmt::Display,
{
println!("{}{}{}", left, value, right);
}
pub fn wrap_with<F, T>(inner: T, should_wrap: bool, wrapper: F)
where
F: FnOnce(&T)
{
if should_wrap {
wrapper(&inner)
}
}
fn main() {
let less = 1;
let more = 100;
if less < more {
wrap_with(will_be_called(), less < more, |inner| print(" ***", inner, "*** "));
wrap_with(will_be_called(), more < less, |inner| print(" ***", inner, "*** "));
} else {
wrap_with(will_not_be_called(), true, |inner| print("wrapped result is: ", inner, ""));
}
}
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