breaking-change-request: ParameterMirror for abstract functions will not provide the default values for optional parameters

[a-siva]

FunctionTypeMirror objects allow reflecting on a function. This object has a method 'parameters' which returns a list of the parameter types of the reflectee. The ParameterMirror object in turn allows reflecting on the formal parameter declaration.

Currently it is possible to reflect on abstract methods and it's formal parameter declaration.

Planned Change

We will not support reflecting on the default parameter values of optional parameters specified on the formal parameter declaration of an abstract method.
defaultValue will always return a Null object
hasDefaultValue will return false

Expected Impact

We expect the impact to be low because of this change as dart2js and flutter do not support dart:mirrors. In addition we always state that the dart:mirrors library is unstable and its API might change.

[mit-mit]

Can you please post to dart-announce?

[a-siva]

Posted.

[mit-mit]

I don't see it? https://groups.google.com/a/dartlang.org/forum/?pli=1#!forum/announce

[mit-mit]

This has now been posted. If anyone has feedback on this breaking change, kindly post comments here.

[mit-mit]

@Hixie @matanlurey @dgrove, please review

[mit-mit]

There appear to be no objections, I think we can land this (after the current stable branch has happened)

[mit-mit]

@a-siva what is the status of this?

[a-siva]

This has landed already.