The "oo::class create <name>" command will fail if the class <name> already exists. This is in contrast to the behaviour of the "proc" command, which overwrites an existing proc. The behavior of "oo::class" makes it awkward to use "package forget; package require" to refresh the contents of a package that defines a class. A package definition like:
namespace boo {
oo::class create Boo {
method boo {} { puts "ouch" }
}
}causes the following problem:
> package require boo
1.0
> package forget boo
> package require boo
can't create object "Boo": command already exists with that name
This can be avoided by splitting the definition of the class as in:
namespace boo {
catch {oo::class create Boo}
oo::define Boo {
method boo {} { puts "ouch" }
}
}but it seems awkward to have to do this for every class that might be used in a package. What is the reasoning behind making it an error to re-"create" a class?