Is it possible to undefine (or redefine would also work) a constant?
um, I don't think so. But if you really need to change or delete a constant, you may want to reconcider what you are using it for. Constants are just that: constant. They are never saposed to change. Just as well, a variable is just that: variable. If the value is ever saposed to change, then it is a variable.
Ya, I know that.
And I know that the "official" word is that it can't be done in PHP.
My situation is that an external library defines a constant that I use in my applications. I know I could just go through and change it's name to avoid conflicts, but this raised more of a theoretical question
Wait until the script is finished executing.
Adrian Schneider - Web Developer
Once a constant is defined you are unable to re-define or un-define it. There is no way I know of to go around this.
From the PHP manual:Once a constant is defined, it can never be changed or undefined.
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