Dynamic class names

Ruby
1

Is it possible to create classes with a dynamic name? Example:

name = “Test”

class name # this fails
def write
puts “TEST”
end
end

puts Object::const_get(name).new.write # => “TEST”

2

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Martin B. wrote:
| Is it possible to create classes with a dynamic name? Example:
|
| name = “Test”
|
| class name # this fails
| def write
| puts “TEST”
| end
| end
|
| puts Object::const_get(name).new.write # => “TEST”
|
|
|
Yes. Here is an overview on metaprogramming, and two ways to create
classes dynamically:

  • – Phillip G.
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3

No… I mean the ‘Name’ of a class or module (that what you get with
object.class.name). The doc of Class::new (ri) describes how it works:

You can give a class a name by assigning the class object to a constant.

…but still that doesn’t allow me to set the initial name when
defining the
class.

I am aware that this can be done using eval with the complete class
definition
as a string - which is also not what I want.

The reason is to avoid name clashes of a larger program. So I am
thinking of
using some central instance to assign names and address specific types
of
classes.

Martin

4

Thanks, that’s what I was looking for.

That example of mine now works:

name = ‘Test’
Object::const_set(name.intern, Class::new do
def write
puts “TEST”
end
end
)
Object::const_get(name).new.write # writes => “TEST”

martin

5

On Wed, Apr 2, 2008 at 11:18 AM, Martin B. [email protected] wrote:

puts Object::const_get(name).new.write # => “TEST”

sure

c = Class::new {
def a; 41 end
}
d = Class::new(c) {
def a; super.succ end
}
d.new.a → 42

HTH
Robert

–
http://ruby-smalltalk.blogspot.com/

Whereof one cannot speak, thereof one must be silent.
Ludwig Wittgenstein