Suggestion Backlog Slog, 8/22/2016

[RyanCavanaugh]

• Allow quoted names in ambient contexts #9846 Allow quoted names in ambient contexts
• Suggestion: --noImplicitBooleanConversion #9702 --noImplicitBooleanConversion flag
• Suggestion: Override protected with private #9677 Allow protected -> private overrides
• Default compiler options #9642 Emit more comprehensive tsconfig.json when using --init
• Suggestion: should non-null assert propagate? #9640 Non-null operator should propagate
• Consider changing default target to ES5 #10117 Change default target to ES5
• Provide a way to alias namespaces #10187 Allow namespace aliases
• Show some elaboration for property not existing in union type #10256 Show elaboration when property is missing in union type
• Allow access to protected class members if the 'this' type of an (extension) function is specified #10302 Allow access to protected class members via this in extension functions
• Un used variable is emmitted while transpiling enums. #4620 Remove unused var in enum emit

[RyanCavanaugh]

Stretch goals

• Narrowing call signatures doesn't work so well #10471 Narrowing of compatible call signatures doesn't work
• [Proposal] Type assertion statement (type cast) at block-scope level #10421 Type assertion in blocks
• Optional parameter with initializer is still considered potentially undefined in function body #10316 Optional parameters with defaults appear nullable in implementation
• Suggestion: output fewer errors for incorrectly implemented interface #10077 Show fewer errors when class fails to implement interface
• Configuration Inheritance #9876 Configuration inheritance
• Method overloading does not work on TSX templates #9703 Overload resolution for JSX SFCs (how?)
• Intersecting discriminated union breaks type narrowing #9919 Intersections of discriminated unions fail to narrow

[RyanCavanaugh]

• Allow quoted names in ambient contexts #9846 Allow quoted names in ambient contexts
  • These can almost always be rewritten
  • 👎 A lot of work for not a lot of payoff
• Suggestion: --noImplicitBooleanConversion #9702 --noImplicitBooleanConversion flag
  • 👎 Idiomatic. Use TSLint if you want to do this
• Suggestion: Override protected with private #9677 Allow protected -> private overrides
  • This allows calls to B from outside B, which is weird
  • 👎 not allowed in other languages either
• Default compiler options #9642 Emit more comprehensive tsconfig.json when using --init
  • Current subset seems random
  • Populate with the defaults
  • 👍 come up with a list of what we want in here
• Suggestion: should non-null assert propagate? #9640 Non-null operator should propagate
  • Not clear what the extent of the assertion is?
  • Would be nice to have some "no really it's not null assertion"
    • But this is really just const xx = x!;
  • Would be nice to have statement/block vs expression assertion areas
  • Can't find room in the syntax for this or the other assertion requests
  • Ideally, just not a problem
• Consider changing default target to ES5 #10117 Change default target to ES5
  • 👍 for 2.1
• Consider allowing access to UMD globals from modules #10178 Allow namespace aliases
  • Get some use cases for this
• Show some elaboration for property not existing in union type #10256 Show elaboration when property is missing in union type
  • 👍 show the "first" unmatching type for whatever value of "first" happens
• Allow access to protected class members if the 'this' type of an (extension) function is specified #10302 Allow access to protected class members via this in extension functions
  • Any access of a protected property through this is necessarily OK
  • Is it allowed to access (in OP example) another instance's protected members?
    • Yes
  • 👍 Treat this: T as being lexically inside T's class declaration for accessibility purposes
• Un used variable is emmitted while transpiling enums. #4620 Remove unused var in enum emit
  • Proposed: make enum emit the same as namespace emit (assign to variable declared before it)
  • Which is actually preferred? Presumably NS
  • 👍 low-pri
• Narrowing call signatures doesn't work so well #10471 Narrowing of compatible call signatures doesn't work
  • Can't figure out anything that would actually work (no coherent way to implement "Treat Functions differently" here)
  • Design Limitation
• [Proposal] Type assertion statement (type cast) at block-scope level #10421 Type assertion in blocks
  • Should in be a type guard?
    • Only works on sealed types
      • But UDTGs assume sealedness anyway
  • Try a PR for in type guards
• Optional parameter with initializer is still considered potentially undefined in function body #10316 Optional parameters with defaults appear nullable in implementation
  • This declaration (mixing ? and initializer) is invalid
• Suggestion: output fewer errors for incorrectly implemented interface #10077 Show fewer errors when class fails to implement interface
  • Accepting PRs if it can be done cheaply / simply
• Configuration Inheritance #9876 Configuration inheritance
  • 👍 and discuss at design meeting
• Method overloading does not work on TSX templates #9703 Overload resolution for JSX SFCs (how?)
  • Doable for simple cases (iterate over union constituents or overload signatures)
  • What to do about T & (U | V) ?
  • Yui to investigate in 2.1