T.string

A scalar. No bare form — there's no natural bound to fuzz a string to, so .whereby({ length }) is required.

T.string.whereby({ length: { min: 1, max: 25 } });
T.string.whereby({ length: { min: { value: 0, exclusive: true }, max: 25 } });

length.min defaults to 0. length counts UTF-16 code units, so the result's .length equals the chosen length exactly.

By default, characters span all Unicode scalar values — the full codespace minus surrogates, so the result is always well-formed UTF-16. Control that with composition:

T.string.whereby({
  length: { min: 8, max: 8 },
  composition: { lowercase: 3, digit: 1 },
});

composition is either a weighting over the built-in classes (lowercase, uppercase, digit, symbol, space) or explicit [weight, source] pairs over arbitrary character sources — a literal string (shorthand for the ranges of its individual characters), a code point range, or a list of ranges.

T.string.as(produce, hints?) layers a custom producer over the schema — see T.opaque.