Readonly<T> not assignable to T with optional properties #12542

Activity

1. Mohamed Hegazy (mhegazy)

   added

   BugA bug in TypeScriptA bug in TypeScript

   on Nov 28, 2016
2. Mohamed Hegazy (mhegazy)

   added this to the TypeScript 2.1.3This milestone has been deleted milestone on Nov 28, 2016
3. Mohamed Hegazy (mhegazy)

   assigned

   Anders Hejlsberg (ahejlsberg)

   on Nov 28, 2016
4. mhegazy commented on Nov 28, 2016

   

   Mohamed Hegazy (mhegazy)

   on Nov 28, 2016

   ContributorAuthor

   More actions

   Some other related examples:

   type T = { a? : number, b: string };
   var y: T = {} as any;
   var x1: Readonly<T> = y; // Error: Property 'a' is optional
   var x2: Partial<Readonly<T>> = y; 
   var x3: Readonly<Partial<T>> = y; // Error: Property 'a' is optional
   var x4: Partial<T> = y;
   var x5: Pick<T, "a"> = y; // Error: Property 'a' is optional

   👍React with 👍1Reacted by Aluan Haddad
5. Anders Hejlsberg (ahejlsberg)

   added

   FixedA PR has been merged for this issueA PR has been merged for this issue

   on Nov 29, 2016
6. Anders Hejlsberg (ahejlsberg)

   closed this as completedin #12563on Nov 30, 2016
7. microsoft

   locked and limited conversation to collaborators on Jun 19, 2018