def _get_build_sources_parameter(self, build_param):
        # returns True if we want to build the missing libraries
        #         False if building is forbidden
        #         A list with patterns: Will force build matching libraries,
        #                               will look for the package for the rest

        if isinstance(build_param, list):
            if len(build_param) == 0:  # All packages from source
                return ["*"]
            elif len(build_param) == 1 and build_param[0] == "never":
                return False  # Default
            elif len(build_param) == 1 and build_param[0] == "missing":
                return True
            else:  # A list of expressions to match (if matches, will build from source)
                return [ref_expr % "%s*" for ref_expr in build_param]
        else:
            return False  # Nothing is built
dataset/ETHPy150Open conan-io/conan/conans/client/command.py/Command._get_build_sources_parameter/swapped operands of `%`