Variable variable

Rails
1

Hi, i also program in php and one of the concepts i miss in ruby is the
“variable variable”

$a=“test”
$$a=“test2”

echo $test will output “test2”

this can be usefull when a field on a form determines which object to
create
example:

$objecttocreate=“car”

$obj=new $$objecttocreate will create a new car object

is this possible in ruby?
i can’t figure it out

2

x = ‘MyModel’
obj = Module.const_get(x).new
obj.class => MyModel

3

I’m new to Ruby and Rails, too. Chris’ example is very cool - I hadn’t
seen
“Module.const_get” before. A less sophisticated (and much more
dangerous)
way to do the same thing would be to use eval:

x = “Foo”
obj = eval("#{x}.new")
obj.class => Foo

Actually, good Rubyists can manage to construct whole classes (and
modules and definitions)
on the fly, not just objects. Cool stuff.

Jim