Adjust to the moving target called the C++ standard. Apparently nowadays it's not allowed to define an explicit copy constructor but not an assignment operator. Consequently, defining the explicit copy constructor in terms of the implicit/automatic assignment operator for general convenience no longer works. Add assignment operators. Caution: not tested with the IBM compiler, but there's no particular reason it shouldn't work.

SYNS=dsl.syn
SRCS=./dsl.cpp query.cpp redirect.cpp screen.cpp symbol.cpp

PROG=dsl
INCDIRS=. $(TOP)/examples/dsl $(TOP)/oldclasslib/include
MYLIBS=$(BUILDTOP)/oldclasslib/source/oldclasslib$(LIBEXT)
AGFILEDEST=here
THISEXAMPLE=dsl

include $(TOP)/mk/prog.mk
include $(TOP)/mk/installexample.mk