Re: deductive databases

Quoth "ken quirici" <kquirici_at_yahoo.com>:
> AFAIK there is no algorithm using recursion that can't be 'emulated'
> by one not using recursion.

Ackermann's function may be an exception; there do exist some fundamentally recursive expressions where "emulation" doesn't work out well.

The normal alternative to recursion is merely to hide it by the use of a stack. (FORTRAN folk know this well, as FORTRAN was very recursion-unfriendly until quite recently.)

And while recursion is an abstraction that can cause confusion to those new to it, the ways of hiding it tends to lead to code that is more opaque than straightforward recursion would have been.

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