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pub trait Is<T> {
fn is(&self, is: T) -> bool;
}
pub trait IfEq<T> {
fn if_eq(&self, is: T) -> bool;
}
pub trait Then<R, F> {
fn then(&self, f: F) -> R
where
F: Fn() -> R;
}
pub trait ThenPrint {
fn then_print(&self, msg: &str) -> String;
}
impl<T> Is<T> for T
where
T: std::cmp::PartialEq,
{
fn is(&self, is: T) -> bool {
*self == is
}
}
impl<T> IfEq<T> for T
where
T: std::cmp::PartialEq,
{
fn if_eq(&self, is: T) -> bool {
*self == is
}
}
impl ThenPrint for bool {
fn then_print(&self, msg: &str) -> String {
if *self {
return msg.to_owned();
}
msg.to_owned()
}
}
impl<R, F> Then<R, F> for bool {
fn then(&self, f: F) -> R
where
F: Fn() -> R,
{
f()
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn it_works() {
assert_eq!(9.if_eq(9).then_print("It works"), "It works".to_owned());
assert_eq!(9.if_eq(9).then(|| "It works"), "It works".to_owned());
assert_eq!(9.if_eq(9).then(|| (0..100).collect::<Vec<_>>().len()), 100);
assert_eq!("alma".if_eq("alma").then(|| "ok"), "ok");
assert_ne!("alma".if_eq("alma").then(|| "ok"), "_ok");
}
}