https://issues.dlang.org/show_bug.cgi?id=7854
Walter Bright <bugzi...@digitalmars.com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|NEW |RESOLVED
CC| |bugzi...@digitalmars.com
Resolution|--- |INVALID
--- Comment #15 from Walter Bright <bugzi...@digitalmars.com> ---
This is actually a feature. I used it to good effect to define a function for
errno:
https://github.com/dlang/druntime/blob/master/src/core/stdc/errno.d#L34
extern (C)
{
ref int _errno();
alias errno = _errno;
}
The actual function in the C runtime library returns an int*, but by making it
a ref int it will automatically dereference in D, enabling the simple use of
`errno` as in C.
Other uses are being able to hook up to functions based on their underlying
representation and bypass the stronger type checking D has. Such as FILE is a
shared type in D, but in C it's just another type. Sending it as extern(C) is
very convenient.
--
