to-regex-range
Pass two numbers, get a regex-compatible source string for matching ranges. Validated against more than 2.78 million test assertions.
is-number
Returns true if a number or string value is a finite number. Useful for regex matches, parsing, user input, etc.
fill-range
Fill in a range of numbers or letters, optionally passing an increment or `step` to use, or create a regex-compatible range with `options.toRegex`
regexp-range
create regex class range string `[一-十]` `[⓪-㊿]` ...