Morganamilo/paru · error

option must be a number

Error message

option {} must be a number

What it means

This is a numeric parse failure thrown from handle_arg (src/command_line.rs), the per-option dispatcher called by parse_arg. It fires when an option is given a value that must be interpreted as a number (a numeric CLI option such as a parallelism/limit flag) and the supplied string cannot be converted to that numeric type. It is a generic validation guard in the argument-handling match: the invalid input is the raw string attached to the offending option on the command line (for example a misspelled number, trailing characters, or an empty value that the option syntax still routed through the value path). The parse aborts with this message rather than silently clamping or defaulting the value.

Solutions

1. Pass a plain integer: `--completioninterval 5`
2. Fix scripts so the interpolated variable is numeric
3. Check the accepted range/type (integer) in the docs

Example fix

// before
paru --completioninterval 30s
// after
paru --completioninterval 30

function is_plain_int(s: string): boolean {
  return /^\d+$/.test(s.trim());
}
// before exec: if (!is_plain_int(interval)) throw new Error('--completioninterval must be a number');

match cli::parse(&args) {
    Err(e) if e.to_string().contains("must be a number") => {
        eprintln!("{} — pass a plain integer, e.g. --completioninterval 5", e);
        std::process::exit(2);
    }
    Err(e) => return Err(e),
    Ok(cmd) => cmd.run(),
}

When it happens

Trigger: Running with a non-numeric value, e.g. `--completioninterval abc`, `--completioninterval 5.5` (if the target integer type rejects it), or an empty string from an empty variable.

Common situations: Config scripts interpolating non-numeric values; users giving a time unit like `30s` or `5m` when only a bare number is accepted; locale-formatted numbers like `1,5`.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• option expects a value
• unknown option
• unknown option
• option does not allow a value
• invalid value ' ' for key ' ', expected

AI-assisted analysis of Morganamilo/paru@9ac3578807 (2026-09-12). Data as JSON: /api/errors/05bece762ec88bf0. Report an issue: GitHub.

Appendix: source

Thrown at src/command_line.rs:212

            Arg::Long("sudoflags") => self.sudo_flags.extend(split_whitespace(value?)),
            Arg::Long("batflags") => self.bat_flags.extend(split_whitespace(value?)),
            Arg::Long("fmflags") => self.fm_flags.extend(split_whitespace(value?)),
            Arg::Long("chrootflags") => self.chroot_flags.extend(split_whitespace(value?)),
            Arg::Long("chrootpkgs") => self
                .chroot_pkgs
                .extend(value?.split(',').map(|s| s.to_string())),
            Arg::Long("rootchrootpkgs") => self
                .root_chroot_pkgs
                .extend(value?.split(',').map(|s| s.to_string())),

            Arg::Long("develsuffixes") => self.devel_suffixes = split_whitespace(value?),
            Arg::Long("installdebug") => self.install_debug = true,
            Arg::Long("noinstalldebug") => self.install_debug = false,

            Arg::Long("completioninterval") => {
                self.completion_interval = value?
                    .parse()
                    .map_err(|_| anyhow!("option {} must be a number", arg))?
            }
            Arg::Long("sortby") => self.sort_by = ConfigEnum::from_str(argkey, value?)?,
            Arg::Long("searchby") => self.search_by = ConfigEnum::from_str(argkey, value?)?,
            Arg::Long("limit") => self.limit = value?.parse()?,
            Arg::Long("news") | Arg::Short('w') => self.news += 1,
            Arg::Long("stats") => self.stats = true,
            Arg::Short('s') => {
                self.stats = true;
                self.ssh = true;
            }
            Arg::Long("order") => self.order = true,
            Arg::Short('o') => {
                self.order = true;
                self.optional = true;
            }
            Arg::Long("removemake") => {
                self.remove_make = YesNoAsk::Yes.default_or(argkey, value.ok())?
            }

View on GitHub (pinned to 9ac3578807)