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