I am struggling to have VS code suggest the list of keys for the below snippet. Could you please help me to get the keys autopopulate?
const myVar : Record<string, string> = {
key1: 'val1',
}
myVar.key2 = "val2",
myVar.key3 = "val3";
myVar. //doesn't populate the keys
You need to actually specify the keys that are possible in your object. As the documentation says, Record is not the right type for you:
Record<Keys, Type>
Constructs an object type whose property keys are Keys and whose property values are Type. This utility can be used to map the properties of a type to another type.
You can do something like this:
interface MyInterface {
key1: string;
key2: string;
key3: string;
}
const myVar : MyInterface = {
key1: 'val1',
key2: '',
key3: '',
}
myVar.key2 = "val2":
myVar.key3 = "val3";
In general, typescript does not track mutations. Except this case. Apart from that, once you defined explicit type for myVar, I mean Record<...>, TS will not infer any properties for you, except the case when you use satisfies operator.
However, if you want to use explicit type Record<string, string> for your myVar and want to mutate it, you can consider using assertion functions
const myVar: Record<string, string> = {
key1: 'val1',
}
myVar.key2 = "val2",
myVar.key3 = "val3";
function mutate<
Obj extends { [prop: string]: string },
Key extends string,
Value extends string
>(obj: Obj, key: Key, value: Value): asserts obj is Obj & Record<Key, Value> {
Object.assign(obj, { [key]: value })
}
mutate(myVar, 'key1', 'val2')
myVar.key1 // val2
I strongly recommend you to avoid mutations in typescript. TS does not like it, see my article
