On Tuesday, 13 September 2016 at 20:36:22 UTC, Steven
Schveighoffer wrote:
On 9/13/16 4:11 PM, Yuxuan Shui wrote:
On Tuesday, 13 September 2016 at 20:00:40 UTC, Steven
Schveighoffer wrote:
Not familiar with C++ lambda. You can always "specify" how to
capture
the data by directly declaring it:
auto foo()
{
int x;
static struct S
{
int x;
}
return S(x);
}
It just feels a bit tedious to do something manually while the
compiler
have enough information to do it for me.
Do what for you? How does it know that you don't want to use a
closure and a reference to that instead?
Note that all the internals for this are implementation
defined. Given sufficient conditions, the compiler could
"cheat" and allocate the data inside the struct itself instead.
For example, if all referenced data was immutable.
-Steve
For example, a common use case might be I want to capture
everything by value. In stead of adding all the fields by hand
and passing them to the constructor, I want the compiler to do it
for me.
i.e. I wish I could (borrowing C++ syntax):
struct A[=] {
...
}
Then the context will be captured by value instead of reference.
