{

Catch::Session session; // There must be exactly one instance

int height = 0; // Some user variable you want to be able to set

// Build a new parser on top of Catch's

using namespace Catch::clara;

auto cli

= session.cli() // Get Catch's composite command line parser

| Opt( height, "height" ) // bind variable to a new option, with a hint string

["-g"]["--height"] // the option names it will respond to

("how high?"); // description string for the help output

// Now pass the new composite back to Catch so it uses that

session.cli( cli );

// Let Catch (using Clara) parse the command line

int returnCode = session.applyCommandLine( argc, argv );

if( returnCode != 0 ) // Indicates a command line error

return returnCode;

// if set on the command line then 'height' is now set at this point

if( height > 0 )

std::cout << "height: " << height << std::endl;

return session.run();