Accessing functions in a module without 'include'

Ruby
1

Usually I work with modules like this:

Defining a module in one file

module M
def f(x)
…
end
end

Using the module in another file

require ‘M’
include M
f(45)

Sometimes I would find it more convenient to not inject
the module’s namespace into the user’s namespace, i.e. to
do it without the include statement. I thought it would
be easy to qualify the foreign function with the module
name:

Using the module in another file

(this does not work)

require ‘M’
M::f(45) # Error: undefined method ‘f’

Maybe I’m thinking to Perlish here. Can it be done what I want
to achieve, and how?

Ronald

2

On Jun 29, 5:25 am, “Ronald F.” [email protected]
wrote:

Usually I work with modules like this:

Defining a module in one file

module M
module_function # <<<<<<<<< HERE
def f(x)
…
end
end

T.

3

Ronald F. wrote:

require ‘M’

(this does not work)

require ‘M’
M::f(45) # Error: undefined method ‘f’

Maybe I’m thinking to Perlish here. Can it be done what I want
to achieve, and how?

Not sure if it’s what you want, but if you define M as follows it works:

module M
def self.f(x)
…
end
end

cheers,
mick

4

end
Thank you, this works perfectly well!

Ronald

5

Defining a module in one file

module M
module_function # <<<<<<<<< HERE
def f(x)
…
end
end

Thank you, this is indeed one solution to my problem (though in the
end, I’m going to stick with Michael H.’ proposal).

Ronald

6

On Jul 2, 5:34 am, “Ronald F.” [email protected] wrote:

Defining a module in one file

module M
module_function # <<<<<<<<< HERE
def f(x)
…
end
end

Thank you, this is indeed one solution to my problem (though in the
end, I’m going to stick with Michael H.’ proposal).

Don’t mention it :slight_smile: BTW, Just to make sure you know, you can’t use
Micheal’s solution if you still want the option of including the
Module elsewhere. In effect using module_function is the same as:

module M
  def self.f(x)
    ....
  end
  def f(x)
    ....
  end
  private :f
end

Probably you’ve already figured that out, but just in case…

T.

7 
  end
  private :f
end

I wasn’t aware that the instance functions would then go private,
but in my case this would be no problem anyway.

Ronald