const auto begin = s.find_first_not_of(kWhitespace);

if (begin == std::string::npos) return "";

const auto end = s.find_last_not_of(kWhitespace);

return s.substr(begin, end - begin + 1);

const std::string trimmed = Trim(line);

const auto head_end = trimmed.find_first_of(kWhitespace);

const std::string head = trimmed.substr(0, head_end);

const std::string rest = head_end == std::string::npos ? "" : Trim(trimmed.substr(head_end));

if (head == ":params") {

if (rest.empty()) {

ParamCommand command;

command.kind = ParamCommand::Kind::kList;

return {.is_param_command = true, .command = command, .error = ""};

}

if (rest == "clear") {

ParamCommand command;

command.kind = ParamCommand::Kind::kClear;

return {.is_param_command = true, .command = command, .error = ""};

}

return {.is_param_command = true, .command = std::nullopt, .error = "expected ':params' or ':params clear'"};

}

if (head != ":param") return {}; // not a parameter command

const auto name_end = rest.find_first_of(kWhitespace);

ParamCommand command;

command.kind = ParamCommand::Kind::kSet;

command.name = rest.substr(0, name_end);

command.expression = name_end == std::string::npos ? "" : Trim(rest.substr(name_end));

if (command.name.empty() || command.expression.empty()) {

return {.is_param_command = true, .command = std::nullopt, .error = "expected ':param <name> <expression>'"};

}

return {.is_param_command = true, .command = command, .error = ""};

std::vector<std::string> names;

names.reserve(params_.size());

for (const auto &[name, value] : params_) names.push_back(name);

return names; // std::map keeps keys sorted

auto map = mg_memory::MakeCustomUnique<mg_map>(mg_map_make_empty(static_cast<uint32_t>(params_.size())));

for (const auto &[name, value] : params_) {

// mg_map_insert copies the key and takes ownership of the value copy.

mg_map_insert(map.get(), name.c_str(), mg_value_copy(value.get()));

}

return map;