Boolean flags

An option becomes a boolean flag when its coerce is coerce.boolean. It takes no value on the command line, and it accepts the --no- prefix.

defineOptions({
  verbose: {
    aliases: ["v"],
    schema: z.boolean().optional(),
    coerce: coerce.boolean,
  },
});

Negation

A flag is true when it appears. The --no- prefix inverts whatever the final value would have been.

--verbose        true
--no-verbose     false

You can also assign a value. The assignment happens first, and then the --no- prefix flips the result.

--verbose=true      true
--verbose=false     false

--no-verbose=true   false   # assigned true, then inverted
--no-verbose=false  true    # assigned false, then inverted

Short flags

Short flags negate the same way, but they cannot take an assigned value:

-v               true
--no-v           false

-v=true          error
-v=false         error

--no-v=true      false
--no-v=false     true

Short boolean flags can be grouped: -rf is the same as -r -f.

Limits

--no- only works on options coerced with coerce.boolean. Using it on anything else fails with ParseErrorCode.InvalidNegationForNonBooleanOption.

Do not name an option in its negated form (noVerbose). The definition check rejects it because it would collide with the negation of verbose.