brisk orchid
would really appreciate help about what exactly @as does ?
specifically why does this work ?
const t1: u8 = 45;
_ = @as(f32,t1);
its able to convert u8 -> f32 using @as
but when I try to do
const r:f32 = @divExact( @as(f32,j),@as(f32,255));
I get an error : error: expected type 'f32', found 'u8'
this problem seems to be fixed by using @floatFromInt but isnt @as supposed to do the conversion ?
hoary hare
@as just provides a result type
same thing as const x: T = does, where T is the result type
nova heart
@as is for safe and unambiguous coercions. If you need to convert to a different type, then a different builtin should be used
For example, here you would use @floatFromInt, since you're converting from an int to a float
thorn sphinx
The first code works because t1 is comptime known
brisk orchid
so use @as when doing comptime conversions between types and
functions like @floatFromInt when doing runtime conversions ?
i see
@as(comptime T: type, expression) T
the docs mention that this function is comptime
lean cloud
@as for any coercion (runtime or comptime), @xFromX for any casting
theres just a special case for coercion being more lenient during comptime, since it can catch it in a compile error
you dont usually need to use @as though, as coercion is something that happens implicitly, like assigning to a variable or passing to a function
when the result type is unknown however, you can either use @as(T, expr) or use another line with const x: T = expr
brisk orchid
i see
that clears it up