On 02.04.2018 08:56, Shachar Shemesh wrote:
On 01/04/18 03:32, H. S. Teoh wrote:
The one nagging question I've been having about pure is: how much are we
actually taking advantage of the guarantees provided by pure?
My problem is that pure do not provide many guarantees.
...
It guarantees that no global state is accessed.
We have
developed very clever ways of extending the traditional definition of
pure and invented creative ways of making more things pure, which is all
great.
Can anyone explain to me what good are the guarantees provided by a
function that is pure but not strictly pure? I couldn't find them.
...
You can use weakly pure functions to compose strongly pure functions.
But AFAIK the only place where it's actually taken advantage of
is to elide some redundant function calls inside a single expression.
You cannot even do that unless the function is strictly pure. For all
D's extension of the pure concept, it weakened, rather than enhanced,
what it means.
...
There is no such weakening.
And perhaps infer uniqueness in some cases for implicit casting to
immutable.
Can you expand on that one?
Shachar
