Announcing TypeScript 2.2

Re:Announcing TypeScript 2.2 by dsp1234 on Wednesday February 22, 2017 @01:12PM (#13707653)

Non-nullable

This is incorrect, as is the announcement. The following is valid.

  class Bar{}
  let foo:object = new Bar()
  foo = null
  foo = undefined

edit:

For the people mentioning, --strictNullChecks. That applies to all types not just object. For example, "let x:string = null" would also be an error. That option applies to any type that is not of type Any/null/undefined, and has been in place since 2.0. In that way, "object" is non-nullable under strictNullChecks just as every other type is.

[ Parent | on HN ]

Re:Announcing TypeScript 2.2 by DanRosenwasser on Wednesday February 22, 2017 @01:28PM (#13707794)

Thanks for catching - I've updated the blog post. I tend to just use `strictNullChecks` by default, as it's typically the best option for any new code. :)

[ Parent | on HN ]

Re:Announcing TypeScript 2.2 by benjaminjackman on Wednesday February 22, 2017 @01:21PM (#13707729)

I think you can use the `--strictNullChecks`[1] compiler option to get that behavior though.

1: https://www.typescriptlang.org/docs/handbook/compiler-option...

[ Parent | on HN ]

Re:Announcing TypeScript 2.2 by realharo on Wednesday February 22, 2017 @01:19PM (#13707701)

I guess it's only so with `strictNullChecks` enabled?

Anyway, TypeScript's `strictNullChecks` in general has a huge hole in that it allows uninitialized properties (https://github.com/Microsoft/TypeScript/issues/8476).

[ Parent | on HN ]

Re:Announcing TypeScript 2.2 by whatever_dude on Wednesday February 22, 2017 @01:20PM (#13707720)

No, object is not a nullable type.

For your code to work, you'd need to run it with strictNullChecks disabled. That's probably what you're doing, since it's the default.

[ Parent | on HN ]

Re:Announcing TypeScript 2.2 by dsp1234 on Wednesday February 22, 2017 @01:42PM (#13707963)

since it's the default.

It's not the default for the command line compiler. Also, all types (except Any/null/undefined) are non-nullable under that option, so that's not what makes object special (it's the no primitive types that is important).

  >tsc test.ts
  >tsc test.ts --strictNullChecks
  >  test.ts(3,1): error TS2322: Type 'null' is not assignable to type 'object'.

[ Parent | on HN ]

Re:Announcing TypeScript 2.2 by whatever_dude on Wednesday February 22, 2017 @01:54PM (#13708095)

> you'd need to run it with strictNullChecks disabled. That's probably what you're doing, since it's the default

I think you misinterpreted my reply. I meant the default is off. That's what your code shows.

[ Parent | on HN ]

Re:Announcing TypeScript 2.2 by dsp1234 on Wednesday February 22, 2017 @01:57PM (#13708137)

I did, sorry about that.

[ Parent | on HN ]

Re:Announcing TypeScript 2.2 by mohamedhegazy on Wednesday February 22, 2017 @01:26PM (#13707777)

Without `--strictNullChecks`, both `undefined` and `null` are in the domain of all types.

[ Parent | on HN ]