Unlock Go’s Hidden Power: How Syntactic Sugar Simplifies Your Code

Syntactic sugar, coined by Peter J. Landin, refers to language syntax that does not add new functionality but makes code easier to write and read, thereby reducing errors.

1. Variadic parameters

In Go, the ellipsis ... after a parameter type denotes a variadic function, allowing any number of arguments of the same type.

func print(values ...string) {
    for _, v := range values {
        fmt.Println("--- > ", v)
    }
}
...
values := []string{"abc", "def", "hig", "klm"}
print(values...)

Another example compares a true variadic function with a slice‑based alternative:

func myFunc1(args ...int) {
    for _, arg := range args {
        fmt.Println(arg)
    }
}
func myFunc2(args []int) {
    for _, arg := range args {
        fmt.Println(arg)
    }
}
myFunc1(2, 3, 4)               // simple call
myFunc2([]int{2, 3, 4})        // requires slice construction

2. Assignment and declaration sugar

The := operator combines variable declaration, assignment, and type inference.

// three ways to assign three integers
var number1, number2, number3 int
number1, number2, number3 = 1, 2, 3

var number1, number2, number3 = 1, 2, 3

number1, number2, number3 := 1, 2, 3

Precautions

:=

can be used only when at least one variable on the left side is new.

It performs only a semantic check; inside loops it behaves like = after the first use.

Both := and = require the number of variables and values to match.

Special cases: map, chan, and type‑inferred functions may return one or two values.

When a map key is absent, the lookup returns the zero value and false.

When a closed channel is read, it returns the zero value and false.

Source: https://www.cnblogs.com/malukang/p/12955983.html