CardBin

The first 6 or 8 digits of a card number, naming its issuer: 424242.

Money and banking; not ordered; since Jadpo 0.1.0.

Make one

Build one from its text, CardBin("424242"), which checks it: text that isn't one breaks format.

text.parse(raw, as: CardBin) reads one from its text; text that isn't one at all fails malformed, such as 4242, 4242424 or 424242424.

Text, JSON and storage

text.from writes its canonical text, the one form text.parse reads back. JSON sends its canonical text as a string.

It is stored in one column named for the field, of type text. 42424242 is stored as '42424242'.

Shown to people

text.format(value, locale:) shows it to people in their locale.

With locale: Locale.en_gb:

Operations

It has the contract's own operations: text.parse, text.from, text.format, json.read, json.write and ==. It isn't ordered, so < and sorting don't take it. Every standard type meets one contract says how they work.