Convert duration to years?

[Dave Chapman via Digitalmars-d-learn]

On Sunday, 15 January 2017 at 03:43:32 UTC, Nestor wrote:
> Hi,
>
> I would simply like to get someone's age, but I am a little 
> lost with time and date functions. I can already get the 
> duration, but after reading the documentation it's unclear to 
> me how to convert that into years. See following code:
>
> import std.stdio;
>
> void getAge(int yyyy, int mm, int dd) {
>   import std.datetime;
>   SysTime t1 = SysTime(Date(yyyy, mm, dd));
>   SysTime t2 = Clock.currTime();
>   writeln(t2 - t1);
> }
>
> int main() {
>   try
>     getAge(1980, 1, 1);
>   catch(Exception e) {
>     writefln("%s.\n(%s, line %s)", e.msg, e.file, e.line);
>   }
> }
>
> Notice getAge should return ubyte instead of void, only I 
> haven't been able to find how to do it. Any suggestion would be 
> welcome.
>
> Thanks in advance.

Does this do what you want?
import std.stdio;

uint getAge(int yyyy, int mm, int dd) {
   import std.datetime;
   SysTime t1 = SysTime(Date(yyyy, mm, dd));
   SysTime t2 = Clock.currTime();
   return( (t2.year - t1.year));
}

void main() {
   auto age = getAge(1980, 1, 1);
   writefln("age is %s", age);
}