问题
According to The Well Grounded Rubyist:
Ruby allows a special form of symbol representation in the hash-key position, with the colon after the symbol instead of before it and the hash separator arrow removed. In other words, this:
hash = { :name => "David", :age => 49 }
can also be written like this:
hash = { name: David, age: 49 }
I have tried the preceding code in ruby 1.8.7 and 1.9.2 - It is not working. What am I doing wrong?
回答1:
The new hash syntax in Ruby 1.9 still requires that strings be quoted, so instead of David you need "David".
Try this:
hash = { name: "David", age: 49 }
If the book used the bare word David without quotation marks, it is wrong. You might be interested in reading some of the other errata.
来源：https://stackoverflow.com/questions/4563766/hash-syntax-in-ruby