See related SO post https://stackoverflow.com/a/72876823/85371
Shared pointer is the problem. The bind<> template argument cannot be a pointer or reference type
There's some information about why pointers are disallowed in
bind<>: boost-ext/di#317
I figured out a working way to bind the dependency:
const auto injector =
di::make_injector(di::bind<ioperation>().to(
[=, &use_sum](const auto& injector) -> op_ptr
{
return use_sum
? sum_creator()
: dot_product_creator(sum_creator());
}) //
);Note that capturing the factory functions by value keeps the DLL around as long as the injector exists. This is safer than capturing by reference. Capturing the
use_sumby reference highlights that the injector is dynamic. If that's not required, then I'd replace the whole injector with:const auto injector = di::make_injector(di::bind<ioperation>().to( use_sum ? sum_creator() : dot_product_creator(sum_creator())) // );
Using compile_n_run.sh:
+ ./cleanup.sh
removed 'application_main'
removed 'libdot_product.so'
removed 'libsum.so'
=> cleaned up!
+ echo '=> Compiling now...'
=> Compiling now...
+ CPPFLAGS='-std=c++14 -fPIC -I /home/sehe/custom/boost-di/include/'
+ LDFLAGS=
+ g++ -std=c++14 -fPIC -I /home/sehe/custom/boost-di/include/ sum.cpp -shared -o libsum.so
+ g++ -std=c++14 -fPIC -I /home/sehe/custom/boost-di/include/ dot_product.cpp -shared -o libdot_product.so
+ LDFLAGS=' -lboost_filesystem -lboost_system -ldl'
+ g++ -std=c++14 -fPIC -I /home/sehe/custom/boost-di/include/ application_main.cpp -o application_main -lboost_filesystem -lboost_system -ldl
+ g++ -std=c++14 -fPIC -I /home/sehe/custom/boost-di/include/ application_di.cpp -o application_di -lboost_filesystem -lboost_system -ldl
+ ./application_main .
[sum_constructor]
[dot_product_constructor]
[sum_constructor]
[sum_constructor]
[dot_product_constructor]
Plugin Name: sum
calculate(1, 2): 3
Plugin Name: dot_product
calculate(1, 2): 5
[~dot_product_destructor]
[~sum_destructor]
[~sum_destructor]
[~dot_product_destructor]
[~sum_destructor]
+ ./application_di . use_sum
[sum_constructor]
name: sum
[~sum_destructor]
+ ./application_di .
[sum_constructor]
[dot_product_constructor]
name: dot_product
[~dot_product_destructor]
[~sum_destructor]
Or more live:
