@formatjs/intl-numberformat/lib/src/get_internal_slots.js

Ponyfill for ES2020 Intl.NumberFormat

// Type-only circular import
var internalSlotMap = new WeakMap();
export default function getInternalSlots(x) {
    var internalSlots = internalSlotMap.get(x);
    if (!internalSlots) {
        internalSlots = Object.create(null);
        internalSlotMap.set(x, internalSlots);
    }
    return internalSlots;
}