const map = reactive(new Map())
map.set('foo', shallowReactive({a : 1})) 
console.log(isShallow(map.get('foo'))) true

map.set('bar', readonly({b : 1})) 
console.log(isReadonly(map.get('foo'))) true

const map = reactive(new Map())
map.set('foo', shallowReactive({a : 1})) 
console.log(isShallow(map.get('foo'))) false

map.set('bar', readonly({b : 1})) 
console.log(isReadonly(map.get('foo'))) false