On 29/03/21 10:33 -0400, Patrick Palka via Libstdc++ wrote:
This rewrites our range adaptor implementation for more comprehensible
error messages, improved SFINAE behavior and conformance to P2281.
The diagnostic improvements mostly come from using appropriately named
functors instead of lambdas in the generic implementation of partial
application and composition of range adaptors, and in the definition of
each of the standard range adaptors. This makes their pretty printed
types of much shorter and more descriptive.
s/types of/types/
The improved SFINAE behavior comes from constraining the range adaptors'
member functions appropriately. This improvement fixes PR99433, and is
also necessary in order to implement the wording changes of P2281.
Finally, P2281 clarified that partial application and composition of
range adaptors behaves like a perfect forwarding call wrapper. This
patch implements this, except that we don't bother adding overloads for
forwarding captured state entities as non-const lvalues, since it seems
it's sufficient to handle the const lvalue and non-const rvalue cases,
given the current set of standard range adaptors. But such overloads
can be easily added if they turn out to be needed.
Tested on x86_64-pc-linux-gnu, does this look OK for trunk?
OK, thanks.
