This crate is exactly what you expect it to be, the pipe operator in Rust.
You can construct a "pipeline" by passing any expression and at least a
single pipe into the ::pipeop::pipe!
macro. There are some special things
you can do but, in its most basic form the macro tries to literally call
your pipe with the item in the pipeline.
const fn add_one(to: i32) -> i32 {
to + 1
}
let result = pipe!(1 |> add_one |> add_one);
assert!(result, 3);
You can invoke methods on the item in the pipeline at any time by
prefixing the pipe with a .
.
This example calls the add
method on the item in the pipelines
with 1
as the single argument.
use std::ops::Add;
pipe!(1 |> .add(1));
You can also use closures as pipes, so you don't have to define a whole new function for every simple operation. Both types of closures are valid, you can have a closure that just evaluates an expression, or you can have a whole block of code.
pipe!("Hello!"
|> .to_uppercase()
|> |item| println!("{}", item)
);
You can also make closure based pipes look a little nicer by using this syntax instead.
pipe!("Hello!"
|> .to_uppercase()
|> item in println!("{}", item)
);
You can of course accept a pattern in this "weird closure".
This example extracts the inner bool
value from the
Test
instance in the pipeline with pattern matching.
struct Test(bool);
let result = pipe!(Test(true) |> Test(it) in it);
assert_eq!(result, true);