Convert string to symbol-able in ruby

Question

Symbols are usually represented as such

:book_author_title

but if I have a string:

"Book Author Title"

is there a built in way in rails/ruby to convert it into a symbol where I can use the : notation without just doing a raw string regex replace?

Answer 1

In Rails you can do this using underscore method:

"Book Author Title".delete(' ').underscore.to_sym
=> :book_author_title

The simpler code is using regex (works with Ruby):

"Book Author Title".downcase.gsub(/\s+/, "_").to_sym
=> :book_author_title

Answer 2

from: http://ruby-doc.org/core/classes/String.html#M000809

str.intern => symbol
str.to_sym => symbol

Returns the Symbol corresponding to str, creating the symbol if it did not previously exist. See Symbol#id2name.

"Koala".intern         #=> :Koala
s = 'cat'.to_sym       #=> :cat
s == :cat              #=> true
s = '@cat'.to_sym      #=> :@cat
s == :@cat             #=> true

This can also be used to create symbols that cannot be represented using the :xxx notation.

'cat and dog'.to_sym   #=> :"cat and dog"

But for your example ...

"Book Author Title".gsub(/\s+/, "_").downcase.to_sym

should go ;)

Answer 3

Rails got ActiveSupport::CoreExtensions::String::Inflections module that provides such methods. They're all worth looking at. For your example:

'Book Author Title'.parameterize.underscore.to_sym