colon placement in Ruby 2.2+

Question

I see colons used two different ways in Ruby

:controller => 'pages'

and then

action: => 'home'

I found an explanation here: http://goo.gl/ZKxKVK it seems that the position doesn't matter, could someone clarify this?

in the second example you can drop the fat arrow – j_mcnally Dec 28 '15 at 20:56 — j_mcnally, Dec 28 '15 at 20:56
also this is a ruby thing not a rails thing. – j_mcnally Dec 28 '15 at 20:56 — j_mcnally, Dec 28 '15 at 20:56

score 1 · Answer 1 · answered Dec 28 '15 at 21:07

1

action: => 'home' is not valid syntax.

It should be action: 'home' or :action => 'home'.

These are equivalent. They generate:

{:action=>'home'}

answered Dec 28 '15 at 21:07

B Seven

Ruby 2.2 accepts action: => 'home' as valid syntax – lasec0203 Dec 29 '15 at 03:56
On Ruby 2.2.3 I get: `{action: =>'home'} SyntaxError: (irb):6: syntax error, unexpected =>` How are you using it? – B Seven Dec 29 '15 at 15:58

score 1 · Accepted Answer · answered Dec 28 '15 at 21:07

1

Mostly it doesn't matter. Since Ruby 1.9 we can use more short form:

h = { a: 1, b: 2}

But there are some situations where you have to use the longest form, e.g.:

h = {1 => 'a', 2 => 'b'}
h = {"One Two" => 1}

answered Dec 28 '15 at 21:07

2 Answers2