fixed slop from segfaulting when options were provided incorrectly

CMakeLists.txt

 
 include_directories("${PROJECT_BINARY_DIR}")
 
-add_definitions(-DSLOP_VERSION="v5.3.33")
+add_definitions(-DSLOP_VERSION="v5.3.34")
 
 # The names have to be unique unfortunately.
 set(EXECUTABLE_NAME "slop")

src/options.cpp

             }
             if ( i == check.name.length()-1 ) {
                 if ( !check.isFlagArgument && argument.find("=") == std::string::npos ) {
-                    throw new std::invalid_argument("Expected `=` after " + arguments[i]);
+                    throw new std::invalid_argument("Expected `=` after " + argument);
                 }
                 if ( check.isFlagArgument && i+3 != argument.length() ) {
                     throw new std::invalid_argument("Trailing characters on flag " + argument );