You can catch errors by error.code. Available codes are:

• diFactory.Error.COULD_NOT_REQUIRE - exception while require(filename) in file(filename) or register().file(filename)
• diFactory.Error.NOT_A_FUNCTION - exception while fn() in register().factory(fn) or invoke(fn)
• diFactory.Error.DEPENDENCY_NOT_FOUND - exception in invoke(fn) or require(name)

var di = diFactory('app');
di.file('/my/file.js', null, function(error) {
	if(error.code === diFactory.Error.COULD_NOT_REQUIRE) {
		// just emit a warning if require failed, but keep the process alive
		logger.warn(error.message);
		return;
	}

	// throw every other error
	throw error;
});