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Ruby Ruby Objects and Classes Build a Bank Account Class Part 4: Printing the register

Why can you write #{name} instead of #{@name} when doing the string interpolation?

Does Ruby infer that name must be instance variable?

1 Answer

Ruby will not infer it is an instance variable, it will actually infer it is a method call if a local variable is not defined from what I read here (depending on where/how this is all happening)


"Local variables begin with a lowercase letter or _. The scope of a local variable ranges from class, module, def, or do to the corresponding end or from a block's opening brace to its close brace {}.

When an uninitialized local variable is referenced, it is interpreted as a call to a method that has no arguments."

It depends on where you are writing it. (The instance variable assignment and the local variable assignment)

Do you have a question on a specific project/with code?

In the video he has the attr_reader :name

which creates the method call

So basically the #{name} is actually calling the get function that returns the instance variable name for that class.

When you write

attr_reader :name

it is similar to defining a function that returns the value for a specific instance variable, such as:

def name