strings.Map(func(r rune) rune {
  if unicode.IsSpace(r) {
    return -1
  }
  return r
},response)

以下是两种功能之间的基准(source data)：

BenchmarkSpaceMap        500       2941575 ns/op      221184 B/op          2 allocs/op
BenchmarkSpaceFieldsJoin         300       4967475 ns/op      524288 B/op          3 allocs/op

package main_test

import (
    "strings"
    "unicode"
    "testing"
)

func SpaceMap(str string) string {
    return strings.Map(func(r rune) rune {
        if unicode.IsSpace(r) {
            return -1
        }
        return r
    },str)
}

func SpaceFieldsJoin(str string) string {
    return strings.Join(strings.Fields(str),"")
}

func BenchmarkSpaceMap(b *testing.B) {
    for n := 0; n < b.N; n++ {
        SpaceMap(data)
    }
}

func BenchmarkSpaceFieldsJoin(b *testing.B) {
    for n := 0; n < b.N; n++ {
        SpaceFieldsJoin(data)
    }
}