util/argparse.lua
author Matthew Wild <mwild1@gmail.com>
Tue, 11 Oct 2022 11:37:55 +0100
changeset 12767 d26eefe98d09
parent 12481 cc84682b8429
child 13062 766152afc1c9
permissions -rw-r--r--
util.dbuffer: Add efficient shortcuts for discard() in certain cases If the buffer is already empty, nothing to do. If we're throwing away the whole buffer, we can just empty it and avoid read_chunk() (which in turn may collapse()). These shortcuts are much more efficient.

local function parse(arg, config)
	local short_params = config and config.short_params or {};
	local value_params = config and config.value_params or {};

	local parsed_opts = {};

	if #arg == 0 then
		return parsed_opts;
	end
	while true do
		local raw_param = arg[1];
		if not raw_param then
			break;
		end

		local prefix = raw_param:match("^%-%-?");
		if not prefix then
			break;
		elseif prefix == "--" and raw_param == "--" then
			table.remove(arg, 1);
			break;
		end
		local param = table.remove(arg, 1):sub(#prefix+1);
		if #param == 1 and short_params then
			param = short_params[param];
		end

		if not param then
			return nil, "param-not-found", raw_param;
		end

		local param_k, param_v;
		if value_params[param] then
			param_k, param_v = param, table.remove(arg, 1);
			if not param_v then
				return nil, "missing-value", raw_param;
			end
		else
			param_k, param_v = param:match("^([^=]+)=(.+)$");
			if not param_k then
				if param:match("^no%-") then
					param_k, param_v = param:sub(4), false;
				else
					param_k, param_v = param, true;
				end
			end
		end
		parsed_opts[param_k] = param_v;
	end
	for i = 1, #arg do
		parsed_opts[i] = arg[i];
	end
	return parsed_opts;
end

return {
	parse = parse;
}