From C to D: issue with arguments for core.stdc.string.memcpy

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On Wednesday, 20 February 2019 at 20:57:26 UTC, Mike Parker wrote:
> On Wednesday, 20 February 2019 at 20:46:42 UTC, Alec Stewart 
> wrote:
>
>>
>> The error
>>
>>     onlineapp.d(42): Error: function 
>> core.stdc.string.memcpy(return scope void* s1, scope 
>> const(void*) s2, ulong n) is not callable using argument types 
>> (char[31], const(char)*, ulong)
>>     onlineapp.d(42):        cannot pass argument 
>> (*s).stack.buffer of type char[31] to parameter return scope 
>> void* s1
>>
>>
>> SO, with all of that; how can I fix this? Do I have to do some 
>> ugly type casting?
>>
>
> You're passing a static array where the function expects a 
> pointer.
>
> memcpy(s.stack.buffer.ptr, input, n);

To expand on this just a bit, in case you're not familiar with D, 
arrays in D do not decay to a pointer like they do in C. You need 
to pass s.stack.buffer.ptr instead.