Initializing an array can be:
- static
- with a known length and make
- using append
Comparison is unfair but sheds some light on the cost. The most efficient is obviously static. Append is extending the array and x5 the make().
The method may depend on your app requirement and/or practical constraints.
src>go test -bench=. ./arrayinit
Results
go version go1.12 windows/amd64
BenchmarkInitArrayStatic-4 2000000000 0.49 ns/op
BenchmarkInitArrayMake-4 20000000 54.6 ns/op
BenchmarkInitArrayAppendStatic-4 5000000 266 ns/op
BenchmarkInitArrayAppend-4 5000000 277 ns/op
PASS