View-Model extension conflict check?

The vm extension idea is excellent and can mitigate a lot of “the library should have this and that” issues of contention.

But, could the DOMVM vm please provide the following function for extending so that conflicts do not silently cause strange effects, perhaps as an argument to the extension function itself?

function extend(nam,val) {
    if(this[nam]!=undefined) { throw "Conflict: Cannot extend view-model with `"+nam+"` - already defined"; }
    this[nam]=val;
    };

Used like this:

domvm.view.extend(function(vm) {
    vm.extend("state",{});

    // Used directly as a property mutation preprocessor; must have no args and return undefined
    var remodel=function() {
        if(!vm.state.redrawPending) {
            vm.state.redrawPending=true;
            setTimeout(function() {
                vm.state.redrawPending=false;
                vm.redraw();
                },0);
            }
        };
    vm.extend("remodel",remodel);
    });

or if an argument:

domvm.view.extend(function(vm,extend) {
    extend("state",{});
    ...

[leeoniya]

But I dream of a future with ready-made DOMVM components that are plug-n-play

You mean some future where domvm has > 5 users? D:

[leeoniya]

didnt think you’d take my simple, not-that-gnarly proposal and go full-java on it, lol.

i also find it bothersome that if i were reading someone elses code, i would have no idea which calls were native and could be found in docs and which are custom extensions authored by the component’s devs.