What does '...' mean in Go function parameters?

Understanding "...Type" in Go

In Go, the "..." syntax denotes a variadic function parameter. This means that the function can accept an arbitrary number of arguments for that parameter.

For example, the append function in Go is defined as:

func append(slice []Type, elems ...Type) []Type

Here, Type is a placeholder for any Go type. This indicates that the append function can accept a variable number of elements of the specified type to be appended to the slice.

An example of using a variadic parameter can be seen in the following code:

<code class="go">func sayHello(name ...string) string {
    message := "Hello"
    for _, n := range name {
        message += " " + n
    }
    return message
}</code>

This function can be called with any number of arguments, and the resulting string will be the concatenation of "Hello" and all the names provided.

In the code you provided, the append function is being used to concatenate two slices. The ... syntax is used to specify that the final parameter, elems, is variadic. This allows you to append an arbitrary number of elements to the slice.

To clarify, the meaning of ...Type in Go is that it specifies a variadic parameter that can accept an arbitrary number of arguments of the specified type.

The above is the detailed content of What does '...' mean in Go function parameters?. For more information, please follow other related articles on the PHP Chinese website!