Append to 'map' result

[Jean-Louis Leroy via Digitalmars-d-learn]

On Tuesday, 4 July 2017 at 23:26:28 UTC, H. S. Teoh wrote:
> On Tue, Jul 04, 2017 at 11:27:25PM +0000, Jean-Louis Leroy via 
> Digitalmars-d-learn wrote:
>> I want to create a range that consists of the result of a map()
>> followed by a value, e.g.:
>> 
>>   int[] x = [ 1, 2, 3];
>>   auto y = map!(x => x * x)(x);
>>   auto z = y ~ 99; // how???
>> 
>> I have tried several variations: convert 99 to a dynamic 
>> array, to a range, convert range to dynamic array (couldn't 
>> even figure that one); to no avail.
> [...]
>
> Try:
>
> 	auto z = chain(y, only(99));

Thanks!

However, when I try to use this construct in my real code, I 
still have a problem:

     // k is a ClassInfo
     chain(map!(i => i.classinfo)(k.interfaces), only(k.base))

meth.d(311): Error: template std.range.chain cannot deduce 
function from argument types !()(MapResult!(__lambda3, 
Interface[]), OnlyResult!(TypeInfo_Class, 1LU)), candidates are:
/usr/include/d/std/range/package.d(795):        
std.range.chain(Ranges...)(Ranges rs) if (Ranges.length > 0 && 
allSatisfy!(isInputRange, staticMap!(Unqual, Ranges)) && 
!is(CommonType!(staticMap!(ElementType, staticMap!(Unqual, 
Ranges))) == void))