DIP 1031--Deprecate Brace-Style Struct Initializers--Community Review Round 1 Discussion

[MoonlightSentinel]

On Thursday, 13 February 2020 at 07:29:00 UTC, Mike Parker wrote:
> This is the feedback thread for the first round of Community 
> Review for DIP 1031, "Deprecate Brace-Style Struct 
> Initializers":

Effectlively this DIP proposes simplifying the compiler - not so 
much the language itself
  - primarily because this feature is used seldomly and provides 
little value. But there are several problem which undermine this 
rationale.

I would argue that this feature is one of the simpler features of 
for beginners to learn. You have a struct, enumerate it's field 
with appropriate values and get an initialized instance. This has 
compelling use cases (which Andre already presented) and were the 
alternatives are much more verbose. This is in conflict with one 
of D's core strengths, writing expressive and clean code.

This leads to the question why this feature is rarely used. The 
current discussion mentions them being type system holes (because 
they circumvent constructors) [1] and their restriction to 
variable initializers [2]. I think we should address these issues 
to increase the usability of the current syntax instead of simply 
deprecating it.

Suggestions:
[1] Deprecate (and soon disallow) brace-style initializers for 
non-PODs
[2] Allow brace-style initializers wherever a corresponding 
struct rvalue is allowed (and can be resolved unambiguously)