Hash syntax in Ruby

ruby hash syntax-error
grigoryvp picture grigoryvp · Dec 30, 2010 · Viewed 24.8k times · Source

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?

Answer

meagar picture meagar · Dec 30, 2010

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.

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