below message log.
CMake Error at /usr/share/cmake-3.7/Modules/FindPackageHandleStandardArgs.cmake:138 (message):
Could NOT find SWIG (missing: SWIG_EXECUTABLE SWIG_DIR)
Call Stack (most recent call first):
/usr/share/cmake-3.7/Modules/FindPackageHandleStandardArgs.cmake:378 (_FPHSA_FAILURE_MESSAGE)
/usr/share/cmake-3.7/Modules/FindSWIG.cmake:63 (FIND_PACKAGE_HANDLE_STANDARD_ARGS)
ruby/CMakeLists.txt:6 (find_package)
below message log.