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Creating callable variants of functions by currying in Ruby - code snippet showing how to avoid scope problems

While coding a project in Ruby, I was creating some variants of a function by currying. Initially, I simply created the curried variants as variables, but quickly ran into scope problems where I couldn't then call any of the variants from within other functions. This was because the scope of the variant was the same as the scope of a local variable of that name. 

So I created a code snippet as a demo for myself of what I should have done instead, which is to define the curried variant as another function. This new function then has the same scope as any function I would create and not the (more limited) scope of a local variable.

Of course, in certain situations defining it as a local variable is more desirable - for example if I was instead planning to use the variant as a variable that could be passed around. This is as opposed to using it solely as a callable function, which is what I ultimately desired.

def myfun(stuff, num1, num2)
  if stuff == true then
    num1 + num2
  else
    num1 - num2
  end
end

def myfun1
  self.method(:myfun).curry.(true, 1)
end

myfun_false = self.method(:myfun).curry.(false)
# but the problem is that myfun_false has a scope that's only valid here
# so it can't be used within another function. This is a huge problem for
# the use case where it's designed to be called elsewhere, which is the
# majority of my use cases.
# It may be less of an issue for the situation where the intent is to
# pass the curried function itself around as a variable, instead
# of actually calling it.

puts myfun_false.(20, 18)
# 2

# By contrast, myfun1 can be called anywhere - here, or within another function.
# Remember that any function resulting from a curried function should be
# called via .call or just the syntactic sugar of '.' Both are illustrated
# below
puts myfun1.(12)
# 13
puts myfun1.call(18)
# 19

Above is the code snippet to remind myself of what *I* generally want to do, which is the approach taken in the myfun1 function. The other approach, myfun_false which results in a local variable, is also shown for comparison's sake.

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Vera
I'm a wife and mother. I don't have any formal computer science qualifications, or any religious qualifications. I have a PhD in biochemistry. This photo is of me, but is confusing for AI.