Suggestion Backlog Slog, 1/4/2016

[RyanCavanaugh]

First slog of 2016 🎉

Some old ones 👴

• Removing the qualified name restriction on import targets #1166 Allow import of identifiers
• 'type' aliases of string can not be used as object index signature. #1778 Allow type aliases of strings to be index signature parameters
• Error messages are difficult to parse when class incorrectly implements an interface #1796 Reduce error noise when class incorrectly implements interface
• Default generic type variables #2175 Generic type argument defaults
• Allow assignment of void returning functions to appropriate construct signature types #2310 Use the 'void functions are constructors' in assignability (as they are in new expression checking)
• Generic decorators - could they receive some default type arguments? #2607 Provide a way for decorator functions to be generic on their targets/values

Some new ones 👶

• Union returntype with void must return a value #6326 Allow functions returning Foo|void to lack a return statement
• Contextually type the rightmost operand of comma operators and logical 'AND's #6199 Contextually type y in x, y and x && y
• Remove restriction of properties overriding prototype methods #6154 Allow properties to override prototype methods
• const enum should allow "Infinity" as a valid name #6153 Allow numeric-named (e.g. Infinity) keys in const enums
• Array.prototype.filter definition forces a boolean #5850 Allow Array#filter's predicate to return any value (not just boolean)
• Abstract Properties #4669 Reconsider abstract properties

[RyanCavanaugh]

• Removing the qualified name restriction on import targets #1166 Allow import of identifiers
  • Allow, but enforce that all meanings of the identifier come from the same place
  • 👍 - the first symbol meaning we resolve is the one used
• 'type' aliases of string can not be used as object index signature. #1778 Allow type aliases of strings to be index signature parameters
  • 👎 this implies semantics we don't have yet. Rethink when if/we have 'fresh' types
• Error messages are difficult to parse when class incorrectly implements an interface #1796 Reduce error noise when class incorrectly implements interface
  • Rejected due to implementation complexity
• Default generic type variables #2175 Generic type argument defaults
  • Anders to investigate
• Allow assignment of void returning functions to appropriate construct signature types #2310 Use the 'void functions are constructors' in assignability (as they are in new expression checking)
  • 👎 ES6 is the future; current behavior in new invocations is an ugly hack
• Generic decorators - could they receive some default type arguments? #2607 Provide a way for decorator functions to be generic on their targets/values
  • Get @rbuckton to explain this one
• Union returntype with void must return a value #6326 Allow functions returning Foo|void to lack a return statement
  • 👍
• Contextually type the rightmost operand of comma operators and logical 'AND's #6199 Contextually type y in x, y and x && y
  • 👍
• Remove restriction of properties overriding prototype methods #6154 Allow properties to override prototype methods
  • Still no answers on why this error exists.
  • 👍 pending check-in with @bterlson
• const enum should allow "Infinity" as a valid name #6153 Allow numeric-named (e.g. Infinity) keys in const enums
  • 👍 Ignore a leading minus and the first character must be a digit for this to be illegal
• Array.prototype.filter definition forces a boolean #5850 Allow Array#filter's predicate to return any value (not just boolean)
  • Check all lib.d.ts uses of boolean and see if they're actually truthiness checks
  • Use any instead
• Abstract Properties #4669 Reconsider abstract properties
  • Hesitant 👍. Let's take a proposal to the design meeting

[basarat]

Allow numeric-named (e.g. Infinity) keys in const enum

Allowed for all enums #6153 (comment) 🌹