Mathematica: Webel ADT pseudo classes: 'Q: Do I have to use these EX$Val scalar "atom" thingies and the EX$Row, EX$RowList, and EX$RowMap? Can't I just use Wolfram Language Lists and Associations?' A: Of course you can also use the basic Wolfram Language!
Mathematica: Webel ADT pseudo classes: An EX$Val has concise methods for testing the type of its wrapped '$$' value: isR, isI, isB, isQ, isS. These may be used in ADT "constructor" type tests.
Mathematica: Webel ADT pseudo classes: The validity of the type of a wrapped '$$' value of an EX$Val may be checked in ADT "constructors" which have type checking utility support. This strategy has been chosen over sub-types of EX$Val.
Mathematica: Webel ADT pseudo classes: There does not seem to be a way to register ::usage specific to a Webel ADT-Method (TagSetDelayed UpValue). The Webel libraries offer method documentation support via the HelpO` class/method registry.
Mathematica: Webel ADT pseudo classes: Webel ADT-Methods support Wolfram Language Options[] as TagSetDelayed UpValues (but there are some pros and cons). Webel ADT-Methods work with the Webel HelpO` class/method registry, including rich help on options.
Mathematica: Webel ADT pseudo classes: «adt:ref» applied to a property indicates that it is resolved by ID through the ADT store using adt$fetch[id]. Use adt$store[adt] for very large ADTs and for cleaner ADT views and easier Notebook development.
Mathematica: Webel ADT pseudo classes: POLICY: Where an ADT-Method uses UUID-driven Once[] caching the trigger argument is a String '$uuid' which MUST have a default None and MUST be the first argument that has a default.
Mathematica: Webel ADT pseudo classes: The SysMLv1 models are supported by custom stereotypes with icons. Some of these indicate OO-similar use of ADT-Methods and departures from formal Abstract Data Type (ADT) definitions.
Mathematica: Webel ADT pseudo classes: POLICY: The ADT-Methods of an ADT-Class are created as TagSetDelayed UpValues using the 'signature' of the ADT-Class and its defining 'pattern' as 1st argument
Mathematica: Webel ADT pseudo classes: CONVENTION: PROVISIONAL: The infix operator for calling ADT-Methods on ADT "objects" is the CircleDot (⊙ in Notebooks). ISSUE: \[CircleDot] is NOT GOOD FOR USE IN IDEs!
Mathematica: Webel ADT pseudo classes: POLICY/DEFINITION: Every "hard coded" definer or defining client of a definer has a corresponding ADT ArchetypeClass. Example ("hard coded"): The definer 'my$def$MY$SmartList' has ArchetypeClass 'MY$SmartList'.
Mathematica: Webel ADT pseudo classes: TIP: Prefer the Decorator Pattern over multiple inheritance of ADT-Method UpValues! (But not because "inheritance is evil" per se, it isn't.) The base ADT libraries make heavy (and very useful) use in inheritance.
Mathematica: Webel ADT pseudo classes: A tricky POLICY & CONVENTION: Client packages MUST access the special "wrapped" primary '$$' via $ContextAliases! The recommended alias is "A`" (which stands of course for ADT).
Mathematica: Webel ADT pseudo classes: POLICY: Multiple inheritance is supported via ONE (only) ADT-Class and one or more ADT-MemberInterfaces (which have no ADT-Method UpValues)
Mathematica: Webel ADT pseudo classes: POLICY: Definer functions MUST return the self-declared or injected 'pattern' that determines the unique "ADT-signature" of the defined ADT class.
Mathematica: Webel ADT pseudo classes: ADTs that define membership of ADT-classes in a domain package have ADT-signature MemberInterface[$$:None] and MUST NOT populate ADT-method UpValues in their definers.
Mathematica: Webel ADT pseudo classes: NAMING CONVENTION: An UpValue that can be invoked on an ADT accepting its unique 'signature' pattern as (at least) 1st argument is called an 'ADT-Method'. They are NOT methods in the general object-oriented sense!
Mathematica: Webel ADT pseudo classes: There is an 'ADT' universal base that has no supers. It "blesses" every other sub-class ADT by populating it with some common ADT-Method UpValues against a signature pattern via the 'adt$def$All[]' definer function.
Mathematica: Webel ADT pseudo classes: DEFINITION/CONVENTION: Functions that populate ADTs with reusable ADT-method UpValues are called 'definers' and include '$def' in the name after a Package scope indicator: Example: adt$def$ADT, my$def$MY$CleverList
Mathematica: Webel ADT pseudo classes: POLICY: Every named concrete Abstract Data Type (ADT) has a ONE unique "signature" (which is the pattern passed to the "definer" functions). To vary a signature, define another unique ADT name.
Mathematica: Webel ADT pseudo classes: POLICY: The Abstract Data Types (ADTs) are stateless functional (although inheritance and overrides are supported), with no caching by default (although there is nice optional caching using CreateUUID[] and Once[]).
