Process-kit

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Hey community,

In the context of building some CLI utilities for private use, I found Foundation's Process API a tad too dynamic. That's great if you want Process to model both "function-like" utilities and interactive applications, but it's not so good if you try to just call grep or build a small pipeline.

This is where my latest project comes in: process-kit.

Basically, it allows you to describe the utility you'd like to use like this:

struct Grep : Proc {
    typealias Input = StringPipe
    typealias Output = StringPipe
    let pattern : String
    func path() throws -> URL {
        // lookup via PATH
        try .findExecutable(named: "grep")
    }
    var arguments: [String] {
        [pattern]
    }
}

And you can write typesafe pipelines like this:

let myProc = Pipeline {
    MyUtil1()
    MyUtil2(MyArgs(), 42)
    MyUtil3("Hello, World!")
    //... all as typesafe as your Procs make it!
}

Both Input and Output are expected to conform to the Tipe protocol ("Typed pIPE"), and if they additionally conform to PipeEncodable and TypeDecodable (which is true for the provided implementations VoidPipe, StringPipe and JSONPipe), you can initialize them with plain swift types or read the stored value as plain swift type.

Enjoy!

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