Intellisense support in 'this' keyword inside an object.

[sant123]

Hi, maybe this is a bug but is not showing any intellisense regarding with the current object.

TypeScript Version: 1.8.0

Code

interface Person {
 name : string;
 lastName : string;
 age: number;

 greet() : string;
}


var People : Person[] = [{
 name : "Santi",
 lastName : "Aguilar",
 age : 21,
 greet : function(){
 return this.name;
 }
}]

Expected behavior:

Offer intellisense for the current object (this)

Actual behavior:

[DanielRosenwasser]

We experimented with inferring the type of this by the surrounding object, but because it broke a lot of existing code (see #8191 and #7801 (comment)), we couldn't add the change.

You'll be able to add an explicit this type in each method in TypeScript 2.0 (check our nightlies with npm install -g typescript@next):

var People : Person[] = [{
 name : "Santi",
 lastName : "Aguilar",
 age : 21,
 // Notice 'this: Person'
 greet : function(this: person) {
 return this.name;
 }
}]

Alternatively, you can add this: this to each method on the Person interface and implicitly have it work:

interface Person {
 name : string;
 lastName : string;
 age: number;

 greet(this: this) : string;
}


var People : Person[] = [{
 name : "Santi",
 lastName : "Aguilar",
 age : 21,
 greet : function() {
 return this.name;
 }
}]

If you ever want to avoid this being typed as any, we've also provided the --noImplicitThis flag, which gives an error when you used this and the type is not inferrable.

[sant123]

Thank you for your answer Daniel Rosenwasser (@DanielRosenwasser) 😄

[ahejlsberg]

See #14141.