There is a code on p. 195 (6.1.3 Schema Validation with Proxies) that isnt working for me.

const validations = new Map()
const validator = {
set(target, key, value) {
if (validations.has(key)) {
return validations[key](value)
}
return Reflect.set(target, key, value)
}
}

I suggest to change return validations[key](value) to validations(key)(value), because of:

1. Map object dont support accessing through [], only through get method.
2. If we return result of validation, we dont actually reach setting value at target[key]. If we just validate value by direct method call of validations object, as I suggesting, we throw error in that method if value isnt valid, or bypass this method in case of valid value and reach setting the value in Reflect.set.