为什么在这里需要分号？

问题描述：

Here is a test Go program:

package main
import fmt "fmt"
func main () {
    ex := "moo cow
";
    fmt.Print (ex)
}

With the semicolon, it compiles. However, if the semicolon is removed, it doesn't:

string.go:5: syntax error near fmt

Any ideas?

Update (March 2012): Newer Go releases are able to compile both forms (with and without the semicolon).

这是一个测试Go程序： p>

  package main \  nimport fmt“ fmt” 
func main（）{
 ex：=“ moo cow 
”; 
 fmt.Print（ex）
} 
  code>  pre> 
 
 使用分号进行编译。 但是，如果删除了分号，则不会： p> 
 
 
 
string.go：5：fmt 
  pre> 
 
 附近的语法错误 ？ p> 
 
 
 更新（2012年3月） strong>：较新的Go版本可以编译两种形式（带和不带分号）。  / p> 
  div>

答

From The Go Programming Language Specification:

Elements of a list of statements are separated by semicolons, which may be omitted only if the previous statement:

ends with the closing parenthesis ")" of a list of declarations; or

ends with a closing brace "}" that is not part of an expression.

答

Well, the answer's technically here: http://golang.org/doc/effective_go.html#semicolons, but it's not very clear. It looks like you can leave semicolons off the end of statements, but not expressions. I think (I'm not certain here) that expressions are anything with an "=" (or ":=") in them (although += seems to be fine in the tutorial?)

为什么在这里需要分号？

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