array splatting for variadic parameters

[Tino]

Sadly, there has been no formal proposal yet - probably, there was to much stress before the Swift 3 release
But there are a lot of links:

[Idea] Passing an Array to Variadic Functions

Hi! Currently, we can’t call a variadic function with an array of arguments. Reference: 1. Passing an array to a function with variable number of args in Swift - Stack Overflow 2. Driven by Code – Medium Consider the following use case: func average(numbers: Double…) -> Double { return sum(numbers) / numbers.count // Error: Cannot convert value of type ‘[Double]’ to expected argument type ‘Double' } func sum(numbers: Double...) -> Double { … } Right now, there are two ways to fix it: …

[Proposal] Variadics as Attribute

Posted a new proposal, feedback appreciated: https://github.com/Haravikk/swift-evolution/blob/2743411af02e3ac6761fbdd780ede1af4cc34ee7/proposals/0000-variadics-as-attribute.md One talking point raised already is the correct location for the attribute (parameter or type); I'm undecided personally as there are arguments for both, probably not an important detail though (core team can make a decision on that I think), since the guidelines on attributes have been debated a few times already. Also…

Explicit array splat for variadic functions

I've been getting annoyed recently writing two copies of several initializers for a library, where composed objects can either take a variadic list of values or an array. E.g. struct Foo<T> { // ... init(values: [T]) { // ... } init(values: T...) { self.init(values: values) } } struct Bar<T> { // ... init(foos: [Foo<T>]) { // ... } init(foos: Foo<T>...) { self.init(foos: foos) } } Basically, if you'd like to give consumers of an API the option to use the variadic initi…