Array Type Interface dotted notation

[S-ed]

interface Interface {
      [id: string]: string;
}

var a:Interface = {
      b: 'foo'
};

a.b = 'bar';

Throws an error:

Property 'b' does not exist on type 'Interface'

Possible to solve? Maybe treat Array index as 'any':

var a:any = {};
a.b= "foobar";

This one is ok.

[mhegazy]

to access the member b you need to define it in the interface. e.g:

interface Interface {
      b: string;
}

var a:Interface;
a.b = 'bar'; // OK

alternatively you can use string indexing to access your property:

interface Interface {
      [id: string]: string;
}

var a:Interface;

a["b"] = 'bar'; // OK, type of a["b"] is defined in the string indexer definition in Interface

if you give a value the type any, it can have any number of properties, and the compiler will not enforce any rules there.