ShoeSize

A shoe size in its system, written as a box writes it: UK 7.5, EU 42.

Commerce and logistics; not ordered; since Jadpo 0.1.0.

Make one

Build one from its fields, ShoeSize { system: ... size: ... }.

text.parse(raw, as: ShoeSize) reads one from its text; text that isn't one at all fails malformed, such as UK 7,5, UK 7.25 or UK 07.

Fields

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 2 columns, each named for the field, _ and its suffix. This is US 9:

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.