more details...
I want to define a new type listing their possible states...
In ada:
type tpColor is blue,green,yellow);
In C (i don't remember very well..):
type tpColor enum={blue,green,yellow}
So, it' the way to asure that a varaible has only one of them...
But, i think that maybe, in PHP it doesn't exist...i don't know
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