typescript compiler bug? knockout.validation.d.ts doesn't compile anymore

Question

I just updated Typescript from v2.3 to v2.4, and now it is giving me an error on the knockout.validation.d.ts lines:

interface KnockoutSubscribableFunctions

        

Answer 1

The problem exists because of differences in types of the:

[key: string]: KnockoutBindingHandler;

And other params:

isValid: KnockoutComputed<boolean>;
isValidating: KnockoutObservable<boolean>;
rules: KnockoutObservableArray<KnockoutValidationRule>;
isModified: KnockoutObservable<boolean>;
error: KnockoutComputed<string>;
setError(error: string): void;
clearError(): void;

The error you got basically says: the KnockoutComputed type can't be assigned to the KnockoutBindingHandler type.

Probably this compile-time checking are improved in TS 2.4, that's why you hadn't had this problem previously.

Your solution works:

[key: string]: any;//KnockoutBindingHandler;

And if you can change this code you may try another a little bit "prettier" solution:

[key: string]: any | KnockoutBindingHandler;

Which might provide you some additional autocomplete help.