Ensure: list what _implements_ a class

[sethladd]

Was https://code.google.com/p/dart/issues/detail?id=16439

'implements' is as common as 'extends'

[keertip]

dartdoc shows implements, extends and mixins.

[bseib]

counter example:

What (known) classes extend the abstract class Type in core?

[sethladd]

I'm not a total expert of this part of the spec, but classes aren't first class. The runtimeType of an instance is of type Type. A class doesn't subclass from Type.

[bseib]

Do I understand the original issue correctly? That the generated Dart docs didn't show what known classes implement the class you're reading about?

For example, the abstract class HashMap:

In the docs I can easily see that it implements Map, but I don't know what classes implement it. (And perhaps that's not what this github issue was about.)

If I grep the sdk sources, I discover that LinkedHashMap implements HashMap.

zbox:/home/hub/bseib/git/bleeding_edge/dart/sdk/lib (master u=)$ grep -r "implements HashMap" ./*
./_internal/compiler/js_lib/collection_patch.dart:class _HashMap<K, V> implements HashMap<K, V> {
./collection/linked_hash_map.dart:abstract class LinkedHashMap<K, V> implements HashMap<K, V> {

It would be useful to see all known implementing classes in the docs. It helps one navigate and understand the relationships of the libraries at our disposal.

[sethladd]

Ah... it sounds like you're asking for "implemented by". Yes, that is useful. Looks like we have this:

[bseib]

Yes, where it says "Implementors" -- I'm looking for that. What's the URL for your example page? Or is this the output of a newer dartdocgen?

[sethladd]

Yes, it's the new output from the dartdoc tool (which is the tool from this repo :)