How to escape a dash "-" in a Ruby symbol?

Question

I'm using jquery-mobile with Ruby On Rails.

I want to create a button link which implies to have data-role="button" appear in the generated HTML.

I've tried:

<%= link_to "Play", game_play_path, :data-role => "button" %>

But then, I get an error

undefined local variable or method `role' for #<#<Class:0x007fdc25668ee8>:0x007fdc25658610>

Is there a way to escape the dash using the :xxx notation or should I just use the "xxx" notation?

(I agree it's a cosmetic question, but I want my code to be consistent and don't like exceptions)

score 96 · Accepted Answer · edited Jul 03 '19 at 05:40

96

Use single quotes around the symbol name, with the colon prefix:

:'data-role' => 'button'

And here is a nice reference on symbols:

http://www.troubleshooters.com/codecorn/ruby/symbols.htm#_What_do_symbols_look_like

After Ruby 1.9 you can also do

'data-role': 'button'

edited Jul 03 '19 at 05:40

Obromios

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answered Dec 12 '11 at 22:51

Andrew Kuklewicz

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Or double quotes - either works fine. Also note that you [can't use a symbol escaped in such a way with the 1.9 alternative hash syntax](http://stackoverflow.com/questions/2134702/ruby-1-9-hash-with-a-dash-in-a-key) – Carl Suster Dec 13 '11 at 14:15
Thanks everyone, I voted for the most complete answers but all the contributions were welcome! :) – Mick F Dec 13 '11 at 15:10
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As a habit, I usually use double quotes for when there will be string interpolation, and single for when the string ought to be immutable. – Andrew Kuklewicz Sep 28 '12 at 15:51

Daniel Ristic · Answer 2 · 2012-10-04T13:19:01.370

If you find the syntax <%= link_to "Play", game_play_path, :"data-role" => "button" %> ugly because it uses the old hash syntax, another way to do it that involves using ruby 1.9 syntax for hashes is to do the following:

<%= link_to "Play", game_play_path, data: {role: "button"} %>

The hash imbrication generates the hyphen between data and role in the html output.

Be cautious because this only works with data-something attributes, but in your case it's a more eye pleasing alternative.

Also, if you have more data-something attributes, you can write them as well in the nested hash:

<%= link_to "Play", game_play_path, data: {role: "button", other1: "value1", other2: "value2"} %>

score 4 · Answer 3 · answered Dec 12 '11 at 22:50

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Wrap it in single quotes:

:'data-role' => "button"

answered Dec 12 '11 at 22:50

mipadi

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score 2 · Answer 4 · answered Dec 12 '11 at 22:50

2

<%= link_to "Play", game_play_path, :"data-role" => "button" %>

answered Dec 12 '11 at 22:50

clyfe

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Or alternatively use a straight string `"data-role"`. No need for it to be a symbol. #codegolf – Ryan Bigg Dec 12 '11 at 22:58

How to escape a dash "-" in a Ruby symbol?

4 Answers4