How to merge multiple strings and int into a single string

I am a newbie in Go. I can't find any official docs showing how to merge multiple strings into a new string.

What I'm expecting:

Input: "key:", "value", ", key2:", 100

Output: "Key:value, key2:100"

I want to use + to merge strings like in Java and Swift if possible.

I like to use fmt's Sprintf method for this type of thing. It works like Printf in Go or C only it returns a string. Here's an example:

output := fmt.Sprintf("%s%s%s%d", "key:", "value", ", key2:", 100)

Go docs for fmt.Sprintf

You can use strings.Join, which is almost 3x faster than fmt.Sprintf. However it can be less readable.

output := strings.Join([]string{"key:", "value", ", key2:", strconv.Itoa(100)}, "")

See https://play.golang.org/p/AqiLz3oRVq

strings.Join vs fmt.Sprintf

BenchmarkFmt-4       2000000           685 ns/op
BenchmarkJoins-4     5000000           244 ns/op

Buffer

If you need to merge a lot of strings, I'd consider using a buffer rather than those solutions mentioned above.