This is the English version of my post at cnblogs.com.

A Question

Given the code bellow:

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struct Book {
    let name: String
}

let book: Book = "Charlotte's Web"

Is there a way to make it work?

So, is there a way to implicitly create a struct from a string literal?

Expressible Literal Protocol

The answer is yes, with the the magic of expressible literal protocol. It’s a suite of protocols which includes:

In this case, adding ExpressibleByStringLiteral conformance can make the implicit instantiation possible.

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extension Book: ExpressibleByStringLiteral {
    init(stringLiteral value: String) {
        self.init(name: value)
    }
}