🚀 go-pugleaf

In article <1990Aug2.170110.28208@rice.edu> preston@titan.rice.edu (Preston Briggs) writes:
> With C, Q, and PL/M, this doesn't hold.

> 	(i := 1) + i is not always equal to i + (i := 1)

Oh, it's worse than that. (i := 1) + i is not always equal to (i := 1) + i,
depending on optimisation level, or (for a sufficiently clever optimiser)
surrounding code. I can even imagine cases where the same expression twice
in a row produces different results.

> Same problems with ++ and -- in C.

And with any function that has a side effect. Like you say...

> Same problem in lots of languages where people write functions
> with side-effects.

As, for example, any object oriented language where objects have internal
state. Like, about all of them. A language that prevents functions from
having side effects is likely to be pretty restrictive. Can you think of
one, other then purely functional languages? Functions couldn't have I/O,
or for that matter call procedures (since procedures can have side effects).
-- 
Peter da Silva.   `-_-'
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<peter@ficc.ferranti.com>