[mercury-users] maybe(T)

[Michael Day]

> Using `maybe(T)' does have an extra level of indirection compared to using
> plain `T' (just as in C, `T *' has an extra level compared to `T').

Okay, so maybe(int) could be represented as an int pointer in C:

	yes(T)		: valid pointer to an integer
	no		: NULL

However the case I am interested in is when T is a pointer itself already,
for example a string or a structure.

	yes(T)		: pointer to a pointer to something
	no		: NULL

It seems that this could be flattened into this:

	yes(T)		: pointer to something
	no		: NULL

and save an unnecessary pointer cell. Any thoughts?

Michael

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