关键在红宝石新的哈希 [英] key in ruby new hash

问题描述

Ruby 1.9.2的新哈希语法存在一个奇怪的问题。如何在1.9.2中将任何Object作为哈希键？

在1.8.7哈希函数中可用：

  a =b
 {a=> 一些，a => 另一个值，：a => 3rd value} 
  

但是在1.9.2>我们不能）

1.9.2哈希：

  {a：some} => {：a =>s} #it转换为旧的散列格式
  

但是

  a =a
 {a：...} ＃这不起作用
 
 {a：some value} =>语法错误，意外的'}'，期望$结束
 from /home/naveed/.rvm /rubies/ruby-1.9.2-p290/bin/irb:16:in`< main>'
 
 {1：s} => 
 
 SyntaxError：（irb）：11：语法错误，意外的'：'，期望tASSOC {1：s} 
  

之后使用冒号： 。 作为键！

任何对象都可以使用箭头 => 。

There is a weird issue with Ruby 1.9.2's new hash syntax. How can I put any Object as key in hash in 1.9.2?

in 1.8.7 hash it works:

a="b" 
{"a" => "some",a => "another value",:a => "3rd value"}

But in 1.9.2 > We can't (or how can we if I'm wrong?")

1.9.2 hash:

{a: "some"} =>  {:a=>"s"} #it convert to old hash format

but

a="a" 
{a: "..."} # This doesn't work

{"a": "some value"} => syntax error, unexpected '}', expecting $end
from /home/naveed/.rvm/rubies/ruby-1.9.2-p290/bin/irb:16:in `<main>'

{1: "s"} =>

SyntaxError: (irb):11: syntax error, unexpected ':', expecting tASSOC {1: "s"}

解决方案

In Ruby 1.9 you are allowed to put colon : only after symbols that are used as keys!

Any object can use the arrow =>, even symbols.

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