[swift-evolution] Lambda function syntax

Brent Royal-Gordon brent at architechies.com
Wed Dec 23 04:21:53 CST 2015

I have to admit I haven't read the entire thread, so maybe I missed discussion of this.

I, too, don't like the `params in code` syntax. After a year and a half with Swift, I now remember it, but it still reads funny, and I see new developers struggle with it frequently. I've also used Ruby quite a bit, but I really don't like the `||` syntax there either.

What I would do is pull the parameters/type signature out of the braces and put a symbol in front of them. For example:

	let names = people.map => person { person.name }

	database.saveRecord(record) => record, error {
		if let record = record {
		else {

`=>` is used here merely because it's been discussed upthread; I actually think it's a little too heavy for this role, but I don't have a great replacement immediately at hand.

A no-parameters closure would not require a `=>`; a bare block would still do there. I suppose the capture list would still go before the parameters, but after the `=>`. Other closure features remain the same—you can still use the `$N` implicit parameters, and you can still use `->` to specify a return value, `()` to surround the parameters, `:` to specify exact types, etc.

Brent Royal-Gordon

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