Using a method as input to another method

[Erick Star]

Hi, I was wondering if it was possible to do something like the
following:

class A

def b
stuff
end

def c
stuff
end

def d(x)
self.x
end
end

Then use thing.d(a) with thing an instance of A?
Basically, given a long list of methods belonging to a class, if you
wanted ruby to apply methods based on the state of the program, how
would you set it up besides doing:

case A
when b
thing.stuff
when c
thing.otherstuff

 

[Robert Klemme]

Hi, I was wondering if it was possible to do something like the
following:

class A

def b
stuff
end

def c
stuff
end

def d(x)
self.x
end
end

You can leave out method d and use send() directly, i.e.

a = A.new
a.sendb)

However:

Then use thing.d(a) with thing an instance of A?
Basically, given a long list of methods belonging to a class, if you
wanted ruby to apply methods based on the state of the program, how
would you set it up besides doing:

case A
when b
thing.stuff
when c
thing.otherstuff

State pattern comes to mind.

http://en.wikipedia.org/wiki/State_pattern

There are a number of options for modeling this besides of state
pattern. Generally any OO approach exploits overriding of methods, i.e.
you have several classes which share a method with identical signature
but different behavior.

Kind regards

robert

 

[Erick Star]

Thank you for your help,
This question is part of a larger something I've been curious about for
a while. I, essentially, want to make a set of rules and basic methods,
then develop a program that can, when given input, determine what
methods to apply and apply them; and, depending on the rules, if it can
generate a new method that would give a more desirable outcome.
Basically, I want to make a program that will have the ability to
reprogram/build on it self.

 

[Matt Harrison]

Thank you for your help,
This question is part of a larger something I've been curious about for
a while. I, essentially, want to make a set of rules and basic methods,
then develop a program that can, when given input, determine what
methods to apply and apply them; and, depending on the rules, if it can
generate a new method that would give a more desirable outcome.
Basically, I want to make a program that will have the ability to
reprogram/build on it self.

It sounds great but I always remember hearing somewhere that
self-modifying code was terrible. I cant remember why, maybe it's the
debugging thats terribly hard.

Anyway, don't let me discourage you, it sounds like fun

Matt