[GD-General] Re: C++ turing complete

[Patrick M D. <pa...@wa...>]

On Sun, 23 Dec 2001, Jesse Jones wrote:

> The difference is that templates are a Turing complete compile time
> language. This is obviously enormously powerful (and awkward because
> templates were never designed to do this). This lets you do all
> manner of things. Here are a few:

Is it true that templates are Turing complete?  I've seen a simulation of
a turing machine in C++ using templates but I've only been able to make
halting programs execute.  My compiler (gcc 2.95-2) complains when it
evaluates a computation state that has already visited.

Maybe gcc doesn't conform to the standard or C++ templates are not Turing
complete?  Even with limitations on the size of the tape and number of
states, it should still be possible to write a (turing) program that does
not halt.

Patrick