On Tuesday, 22 December 2020 at 14:27:02 UTC, ag0aep6g wrote:
On 22.12.20 04:56, 9il wrote:
6. Algebraic type subsets are supported by `get`,
`trustedGet`, `_is`, and `this` primitives. You can operate
with algebraic subset as with the type of the original
typeset. [1]
"trustedGet" - That name smells of a safety violation. And
indeed (compile with `-release`):
----
import mir.algebraic;
import std.stdio;
void main() @safe
{
immutable int* x = new int(42);
Variant!(size_t, int*) v;
v = cast(size_t) x;
auto p = v.trustedGet!(int*); /* uh-oh */
*p = 13; /* mutating immutable */
writeln(*x); /* prints "13" */
}
[snip]
For
v = cast(size_t) x;
I thought @safe prevented explicitly casting an immutable to a
mutable, but the code below seems to suggest it is ok in this
case...
void main() @safe
{
immutable x = 32;
auto v = cast(size_t) x;
}
