What are the differences between Ruby lambda functions and procs?

What are the differences between Ruby lambda functions and procs?

In Ruby, both lambdas and procs are used to create anonymous functions, but they have some key differences. Lambdas check the number of arguments passed to them, while procs do not. Additionally, lambdas return control to the calling method, whereas procs return from the method they were defined in.

Can you give me an example of each?

Sure! Here's a simple example:

For a lambda:

my_lambda = ->(x) { x * 2 }
puts my_lambda.call(5)  # Outputs: 10

For a proc:

my_proc = Proc.new { |x| x * 2 }
puts my_proc.call(5)  # Outputs: 10

Notice how both can be called similarly, but their behavior differs in terms of argument handling.

What happens if I pass the wrong number of arguments to a lambda?

If you pass the wrong number of arguments to a lambda, it will raise an ArgumentError. For example, if you call my_lambda.call(5, 10), you'll get an error because the lambda expects only one argument.

And what about procs?

Procs are more lenient. If you pass the wrong number of arguments to a proc, it will not raise an error; instead, it will assign nil to any missing arguments. For example, calling my_proc.call will return nil.