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Reflection: Order of fields guaranteed?
Oct 21, 2016
Nick Sabalausky
Oct 21, 2016
Stefan Koch
Oct 22, 2016
Michael Coulombe
October 20, 2016
Gravatar of Nick SabalauskyPosted by Nick SabalauskyReply
Nick Sabalausky
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When using reflection to obtain the fields of a class/struct, is there any guarantee that the order is the same as the order the fields are defined?
October 21, 2016
Gravatar of Stefan KochPosted by Stefan Koch
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On Friday, 21 October 2016 at 01:34:44 UTC, Nick Sabalausky wrote:
> When using reflection to obtain the fields of a class/struct, is there any guarantee that the order is the same as the order the fields are defined?

Yes they should always come in lexical order.
October 22, 2016
Gravatar of Michael CoulombePosted by Michael Coulombe
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On Friday, 21 October 2016 at 01:51:44 UTC, Stefan Koch wrote:
> On Friday, 21 October 2016 at 01:34:44 UTC, Nick Sabalausky wrote:
>> When using reflection to obtain the fields of a class/struct, is there any guarantee that the order is the same as the order the fields are defined?
>
> Yes they should always come in lexical order.

For classes, the spec disagrees, even though it might be true using current compilers.

https://dlang.org/spec/class.html#fields

"The D compiler is free to rearrange the order of fields in a class to optimally pack them in an implementation-defined manner. ... Explicit control of field layout is provided by struct/union types, not classes."