Non-English characters in code - "character 0x2212 is not a valid token"

[sigod via Digitalmars-d-learn]

On Thursday, 28 January 2016 at 13:26:27 UTC, Andrea Fontana 
wrote:
> On Thursday, 28 January 2016 at 13:18:55 UTC, pineapple wrote:
>> I experimented with using the character 'ħ' in a variable 
>> name, and wasn't terribly surprised when the compiler didn't 
>> like it. What did surprise me is that I still got a compile 
>> error even when the character was in a comment. Is there any 
>> way to make dmd not get fussy about unicode?
>
> Hmmm it's strange: I think d should support unicode on both 
> comment and vars name.
>
> This code works for me ;)
>
> float distance(T)(T from, T to)
>       {
>          import std.math;
>
>          auto toRadians = (float dec) => dec/180.0f*PI;
>
>          auto R = 6371;
>          auto φ1 = toRadians(from.lat);
>          auto φ2 = toRadians(to.lat);
>          auto Δφ = toRadians(to.lat-from.lat);
>          auto Δλ = toRadians(to.lng-from.lng);
>
>          float a = sin(Δφ/2) * sin(Δφ/2) + cos(φ1) * cos(φ2) * 
> sin(Δλ/2) * sin(Δλ/2);
>          float c = 2 * atan2(sqrt(a), sqrt(1-a));
>
>          return R * c;
>
>       }

What compiler version do you use?

I tried to compile your code on dpaste (2.070.0) and got this:

	/d213/f100.d(8): Error: character '\' is not a valid token
	/d213/f100.d(9): Error: character '\' is not a valid token
	/d213/f100.d(10): Error: character '\' is not a valid token
	/d213/f100.d(10): Error: character '\' is not a valid token
	/d213/f100.d(11): Error: character '\' is not a valid token
	/d213/f100.d(11): Error: character '\' is not a valid token
	/d213/f100.d(13): Error: character '\' is not a valid token
	/d213/f100.d(13): Error: character '\' is not a valid token
	/d213/f100.d(13): Error: found 'u03c6' when expecting ','
	/d213/f100.d(13): Error: expression expected, not '/'
	/d213/f100.d(13): Error: found '2' when expecting ','
	/d213/f100.d(13): Error: character '\' is not a valid token
	/d213/f100.d(13): Error: character '\' is not a valid token
	/d213/f100.d(13): Error: found 'u03c6' when expecting ','
	/d213/f100.d(13): Error: expression expected, not '/'
	/d213/f100.d(13): Error: found '2' when expecting ','
	/d213/f100.d(13): Error: character '\' is not a valid token
	/d213/f100.d(13): Error: character '\' is not a valid token
	/d213/f100.d(13): Error: character '\' is not a valid token
	/d213/f100.d(13): Error: character '\' is not a valid token