On Wednesday, 14 March 2018 at 15:17:54 UTC, Jonathan M Davis
wrote:
On Wednesday, March 14, 2018 13:36:51 Andre Pany via
Digitalmars-d-learn wrote:
[...]
Well, I think that you have two issues here:
1. Struct literals work in only a few, specific circumstances.
Why, I don't know, but IIRC, someone was writing a DIP to fix
that, and that may or may not fix this case. So, as I
understand it, it's not all that hard to run into places where
they don't work (I confess that I never use them, because I
don't like them any more than I like the fact that struct
constructors are implicitly declared if you don't declare them,
which has caused me bugs when changing the members fo a struct;
both are misfeatures IMHO, though obviously not everyone agrees
on that point).
2. In general in D, the type of an expression is not inferred
based on where it's used. There are a few exceptions where
literals are involved, but in general, if you have something
like
A a = expression;
expression has to evaluate correct on its own without taking A
into account. The fact that something like
Bar b = {s: "str"};
compiles is actually a bit of an oddity in D's semantics in
that respect. So, the fact that it works at all is a bit of a
special case, and clearly, they didn't get everything. My guess
is that the problem is that the dynamic array literal needs a
type, but the compiler is not set up to figure out what type
that is based on the fact that it's being used in a struct
literal.
- Jonathan M Davis
Thanks for the information. As it works fine for dynamic arrays
and the coding
in the compiler seems identical for arrays and associative arrays
I really
wonder why it not work.
Although I really anticipate the DIP, this can be solved as bug
fix.
The chances to solve this a bug fix are much higher than getting
the DIP implemented
in near future (unfortunately).
Kind regards
André
