return type of std.algorithm.mutation.reverse changed for good?

[Steven Schveighoffer]

On 5/24/18 8:08 AM, rikki cattermole wrote:
> On 25/05/2018 12:06 AM, biocyberman wrote:
>> I am testing with DMD 2.078.2 locally. This tiny snippet works on 
>> dlang's online editor: https://run.dlang.io/is/nb4IV4
>>
>> But it does not work on my local dmd.
>>
>> import std.algorithm.mutation;
>> import std.stdio;
>> char[] arr = "hello\U00010143\u0100\U00010143".dup;
>> writeln(arr.reverse);
>>
>> Error: template std.stdio.writeln cannot deduce function from argument 
>> types !()(void)
>>
>> The document says reverse returns a range: 
>> https://dlang.org/phobos/std_algorithm_mutation.html#reverse
> 
> https://docarchives.dlang.io/v2.078.0/phobos/std_algorithm_mutation.html#reverse 
> 

This doesn't quite tell the whole story.

An array used to have a .reverse property that the compiler implemented, 
which returned the array after reversing it. So in history, this 
actually worked without std.algorithm.

You get a nice history of what happens using "all dmd versions" on 
run.dlang.io. If you remove the "mutation" part from the import, you get:

Up to      2.071.2: Success with output: 𐅃Ā𐅃olleh
2.072.2 to 2.074.1: Success with output:
-----
onlineapp.d(6): Deprecation: use std.algorithm.reverse instead of 
.reverse property
𐅃Ā𐅃olleh
-----

            2.075.1: Failure with output:
-----
onlineapp.d(6): Error: template std.stdio.writeln cannot deduce function 
from argument types !()(void), candidates are:
/path/to/dmd.linux/dmd2/linux/bin64/../../src/phobos/std/stdio.d(3553): 
       std.stdio.writeln(T...)(T args)
-----

2.076.1 to 2.077.1: Failure with output:
-----
onlineapp.d(6): Error: template std.stdio.writeln cannot deduce function 
from argument types !()(void), candidates are:
/path/to/dmd.linux/dmd2/linux/bin64/../../src/phobos/std/stdio.d(3571): 
       std.stdio.writeln(T...)(T args)
-----

            2.078.1: Failure with output:
-----
onlineapp.d(6): Error: template std.stdio.writeln cannot deduce function 
from argument types !()(void), candidates are:
/path/to/dmd.linux/dmd2/linux/bin64/../../src/phobos/std/stdio.d(3657): 
       std.stdio.writeln(T...)(T args)
-----

Since      2.079.0: Success with output: 𐅃Ā𐅃olleh

-Steve