30 Dec
2011
30 Dec
'11
3:58 p.m.
Donn Cave
That's why we use terms in a sense that apply meaningfully to computer programming languages in general and Haskell in particular. To do otherwise - for example to insist on a definition of "pure" that could not even in principle apply to any useful programming language, or a definition of "side effect" that would have to apply every time a program does anything - seems to me like an inane waste of time, to put it mildly.
When one questions accepted definitions or beliefs, it is the sign of their vagueness. To be honest, the definitions of “side effect” and “purity” are vague indeed. I hope that eventually (probably in this very discussion) they will be refined.