A Swift library to write Emacs plugins in Swift!
Emacs Swift module provides a convenient API for writing dynamic modules for Emacs in Swift. It marries a dynamic nature of Emacs Lisp with strong static typization of Swift and hides the roughness of the original C API together with harder aspects of that language such as a lack of closures and manual memory management. It also translates Emacs Lisp errors and Swift exceptions into each other.
EmacsSwiftModule allows you to call functions from Emacs Lisp using Swift's own types.
let two: Int = try env.funcall("+", with: 1, 1)
assert(two == 2)
try env.funcall("message", with: "%S %S", "Hello", 42)And define your own Lisp functions out of Swift closures
try env.defun("foo") {
(x: Int, y: Int) in x + y
}
try env.defun("bar") {
(input: [String]) in input.joined(separator: ", ")
}that can be easily used in Emacs Lisp
(foo 1 1) ;; => 2
(bar ["Hello" "World"]) ;; => "Hello, World"It handles errors on both sides so the user can almost always simply ignore them.
try env.defun("always-throws") { (x: Int) throws in
throw MyError(x: x)
}
try env.defun("calls-afdsiufs") {
(env: Environment) in
do {
try env.funcall("afdsiufs", with: 42)
} catch EmacsError.signal {
print("Whoops! It looks like 'afdsiufs' doesn't exist!")
}
}And on the Lisp side too
(always-throws 42) ;; => raises (swift-error "Swift exception: MyError(x: 42)")
(calls-afdsiufs) ;; => nil because we caught the errorThe same happens when a type requirement expected in Swift is not met.
(foo "Hello" "World") ;; => raises (wrong-type-argument numberp "Hello")Full documentation of the package can be found here: https://savchenkovaleriy.github.io/emacs-swift-module/documentation/emacsswiftmodule/
Add the following line to you package dependencies:
.package("https://github.com/SavchenkoValeriy/emacs-swift-module.git", from: "1.3.4")Or add "https://github.com/SavchenkoValeriy/emacs-swift-module.git" directly via Xcode.
All contributions are most welcome!
It might include any help: bug reports, questions on how to use it, feature suggestions, and documentation updates.