Symbol Set - modelint/types GitHub Wiki

This constraint corresponds to the concept of a set or an enumerated type as an implementation.

The platform independent concept, however, is simply a set of names that we call Symbols.

So a Symbol Set is constrained, not by narrowing its scope, but by specifying a set of Symbols.

One way to think of this is to imagine Symbol Set as the universe of all possible Symbols and that we narrow it down by enumerating the set of assignalbe Symbols.

To define colors of a traffic signal we could do this:

Signal

value :: Symbol Set( 'red', 'yellow', 'green' )

Here we have a single component named "value" that constrains the Symbol Set Base Type to a set that holds only the enumerated color names.

Identifiers

1. Component + User type

Attributes

No non-referential attributes.