Golang：在一行上堆叠多个方法调用

Question

Getting started with Go. I'm trying to write a function that title cases a first name then caps the second. Why can't I stack method calls as below?

(The reason why I want to put a .ToLower before is because the .Title only caps the first letter leaving the rest unchanged)

package main

import (
  "fmt"
  "strings"
)

func main() {
  firstName := "mElVIn"
  lastName := "themelvINATor"
  fmt.Println(nameCap(firstName, lastName))
}

func nameCap(s1, s2 string) (str1, str2 string) {
  s1 = strings.ToLower(s1).Title(s1)
  s2 = strings.ToUpper(s2)

  return s1, s2
}

Answer 1

You could try to do something like this (modify for your use case, I'm not entirely sure the output you're trying to get):

type myString string

func main() {
    firstName := "mElVIn"
    lastName := "themelvINATor"
    fmt.Println(nameCap(firstName, lastName))
}

func (s myString) Title(ss string) string {
    return strings.Title(ss)
}

func nameCap(s1, s2 string) (str1, str2 string) {
    s1 = myString(strings.ToLower(s1)).Title(s1)
    s2 = strings.ToUpper(s2)

    return s1, s2
}

FWIW, there's nothing wrong with doing it without chaining:

func nameCap(s1, s2 string) (str1, str2 string) {
    s1 = strings.ToLower(s1)
    s1 = strings.Title(s1)
    s2 = strings.ToUpper(s2)

    return s1, s2
}

GoPlay: http://play.golang.org/p/BcJTuBRqbx