@trusted considered harmful

[Jonathan M Davis]

On Saturday, July 28, 2012 22:52:32 David Nadlinger wrote:
> Maybe it would be a good idea to also allow
> `@trusted(emplace!S)(mem, cast(S)(*_range).save)`, with semantics
> similar to TRUSTED? Or even applying @trusted to arbitrary
> expressions, similar to `checked` in C#?

Even the cast is unsafe. Basically, that entire line is @system and needs to 
be @trusted except for (*_range).save. Attribute inferrence needs to be used 
on that portion. So, aside from inventing yet more syntax like

@trusted { emplace!S(mem, cast(S)@infer{(*_range).save}); }

I don't know how you'd avoid the code duplication here. But at least with 
@trusted blocks, it can be reduced to a single line rather than having to 
duplicate the whole function.

- Jonathan M Davis