Initialise dynamic array in array of structures

[cym13 via Digitalmars-d-learn]

On Wednesday, 22 June 2016 at 08:06:26 UTC, ketmar wrote:
> On Wednesday, 22 June 2016 at 06:43:12 UTC, Paul wrote:
>> Why is initialisation via {} bad (in simple terms please :D)?
>
> first, it is buggy. i.e. it doesn't always call postblit[1]. 
> second, it's syntax is the same as the syntax of argument-less 
> lambda, which makes it context-dependent -- so reader has to 
> make some mental efforts to find out if it is really lambda or 
> struct initialization.
>
> for me, it is enough to see it as bad. and for some other 
> people too. ;-)
>
>
> [1] https://issues.dlang.org/show_bug.cgi?id=16146

On the other hand I don't see why you'd expect {} to call 
postblit at
all.  Postblit is meant for copy construction while here (with {})
there is no copy, just an initialization. And actually the 
"verbose"
way doesn't call postblit either:


import std.stdio;

struct Coord {
     int x, y;

     this(this) { writeln("Postblit (", x, ",", y, ")"); }
}

void main(string[] args) {
     writeln("Building a");
     Coord a = {1, 3};

     writeln("Building b");
     Coord b = Coord(4, 2);
}

/*
  (fcn) sym._Dmain 78
; var int local_14h @ ebp-0x14
; var int local_10h @ ebp-0x10
; var int local_ch @ ebp-0xc
; var int local_8h @ ebp-0x8
; var int local_4h @ ebp-0x4
; DATA XREF from 0x08078f13 (sym.main)
0x080786e0   push ebp
0x080786e1   mov ebp, esp
0x080786e3   sub esp, 0x14
0x080786e6   mov dword [ebp - local_14h], ebx
0x080786e9   mov ecx, str.Building_a
0x080786ee   mov eax, 0xa
0x080786f3   push ecx
0x080786f4   push eax
0x080786f5   call 
sym._D3std5stdio16__T7writelnTAyaZ7writelnFNfAyaZv
; Construction of 'a'
0x080786fa   mov dword [ebp - local_10h], 1
0x08078701   mov dword [ebp - local_ch], 3
0x08078708   mov edx, str.Building_b
0x0807870d   mov ebx, 0xa
0x08078712   push edx
0x08078713   push ebx
0x08078714   call 
sym._D3std5stdio16__T7writelnTAyaZ7writelnFNfAyaZv
; Construction of 'b'
0x08078719   mov dword [ebp - local_8h], 4
0x08078720   mov dword [ebp - local_4h], 2
0x08078727   xor eax, eax
0x08078729   mov ebx, dword [ebp - local_14h]
0x0807872c   leave
0x0807872d   ret
*/

No postblit.