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/**
* The goal of this file is to "allocate" references
* via `alloc(ref)` and return a "pointer" as unique id.
* The reference is held in memory until that "pointer"
* is passed to `dealloc(ptr)` hence freed.
*/
let i = 0;
const ids = new Map;
const values = new WeakMap;
/**
* Create once a unique identifier that can easily travel or be serialized.
* It traps the reference until that identifier is passed to `dealloc` helper.
* @param {object | function} value a reference to relate via a unique identifier
* @returns {number} the unique identifier for the reference
*/
export const alloc = value => {
let id = values.get(value);
if (id == null) {
/* c8 ignore next */
while (ids.has(id = i++));
ids.set(id, value);
values.set(value, id);
}
return id;
};
/**
* Free any previously stored reference associated to the unique identifier.
* @param {number} id the unique identifier previously used to allocate memory
* @returns {boolean} `true` if the identifier was known and successfully freed
*/
export const dealloc = id => {
const value = ref(id);
if (value) {
ids.delete(id);
values.delete(value);
}
return !!value;
};
/**
* Return any previously stored reference associated to the unique identifier.
* @param {number} id the unique identifier previously used to allocate memory
* @returns {object | function | null} the identifier related reference, if any
*/
export const ref = id => ids.get(id);
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