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class TupleMap<Key extends readonly any[], Value> { | |
identifierMap = new Map<any, [number, number]>() | |
internalEntries = new Map<string, readonly [Readonly<Key>, Value]>() | |
lastId = 0 | |
addKey(key: Readonly<Key>) { | |
const { identifierMap } = this | |
return key.map(item => { | |
let entry = identifierMap.get(item) | |
if (!entry) identifierMap.set(item, entry = [this.lastId++, 0]) | |
entry[1]++ | |
return entry[0] | |
}).join('/') | |
} | |
keyToString(key: Readonly<Key>) { | |
const { identifierMap } = this | |
const ids: number[] = [] | |
for (const item of key) { | |
const entry = identifierMap.get(item) | |
if (!entry) return | |
ids.push(entry[0]) | |
} | |
return ids.join('/') | |
} | |
deleteKey(key: Readonly<Key>) { | |
for (const item of key) { | |
const entry = this.identifierMap.get(item)! | |
entry[1]-- | |
if (entry[1] === 0) this.identifierMap.delete(item) | |
} | |
} | |
set(key: Readonly<Key>, value: Value) { | |
let skey = this.keyToString(key) | |
if (skey == null || !this.internalEntries.has(skey)) skey = this.addKey(key) | |
this.internalEntries.set(skey, [key, value]) | |
return this | |
} | |
get(key: Readonly<Key>) { | |
const skey = this.keyToString(key) | |
if (skey != null) return this.internalEntries.get(skey)?.[1] | |
} | |
has(key: Readonly<Key>) { | |
const skey = this.keyToString(key) | |
return skey != null && this.internalEntries.has(skey) | |
} | |
delete(key: Readonly<Key>) { | |
const skey = this.keyToString(key) | |
if (skey != null && this.internalEntries.delete(skey)) { | |
this.deleteKey(key) | |
return true | |
} | |
return false | |
} | |
[Symbol.iterator]() { | |
return this.entries() | |
} | |
*entries(): IterableIterator<readonly [Readonly<Key>, Value]> { | |
for (const [, entry] of this.internalEntries) yield entry | |
} | |
*keys(): IterableIterator<Readonly<Key>> { | |
for (const [, [key]] of this.internalEntries) yield key | |
} | |
*values(): IterableIterator<Value> { | |
for (const [, [, value]] of this.internalEntries) yield value | |
} | |
forEach(f: (value: Value, key: Readonly<Key>) => void) { | |
for (const [, [key, value]] of this.internalEntries) f(value, key) | |
} | |
get size() { | |
return this.internalEntries.size | |
} | |
clear() { | |
this.lastId = 0 | |
this.identifierMap.clear() | |
this.internalEntries.clear() | |
} | |
} |
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