Ruby symbol naming

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I am currently reviewing a clients code base for the company I am interning for. The API is built with Ruby on Rails. I am new to Ruby, but have programmed in other languages, so looking through the code (and some tutorials), I have been able to understand most of what is going on, but there is a line that looks like the code below that is throwing me off. Why do the names of the symbols have equals in front? This feels illegal, but ruby is kinda cool. Thank you for your help.

delegate :name=, :description=, :tags=, to: :user

ruby-on-rails ruby
2 Answers

Another point: In Ruby, as a pattern you don't use the prefixes set or get, instead you use just the attribute name for the get and suffix = for the set. Example: setName and getName methods would be name= and name respectively.

Ruby allows you to use the setter method in these sintaxes: obj_instance.name = 'Name' (You can omit the () and use space before caracteres like =) or obj_instance.name=('Name').

user_50611530

A ruby symbol has very few restrictions concerning the characters it can have, and it's mainly linked to the "easy" representation we usually choose.

It's totally possible to have the following symbols:

:"hello/world"
:€
:"a+b"

It becomes a bit trickier when the symbol is used to represent a method, because we like the easy syntax that comes with it, but it's actually the same as sending the symbol using e.g. public_send:

foo.public_send(:"a+b")

This code will work if you define a method named :"a+b". Of course, you can't define it with the usual def, but it's still possible.

Now, some methods such as name= offer an additional semantic, so that the following are equivalent:

object.name = "Fubar"
object.send(:name=, "Fubar")
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