blob: 098ce7ac14d85808ebc7ca2de83e1fb75a99058e (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
|
/*
* SPDX-FileCopyrightText: 2024 Linnea Gräf <nea@nea.moe>
*
* SPDX-License-Identifier: GPL-3.0-or-later
*/
package moe.nea.firmament.util
fun <K, V> mutableMapWithMaxSize(maxSize: Int): MutableMap<K, V> = object : LinkedHashMap<K, V>() {
override fun removeEldestEntry(eldest: MutableMap.MutableEntry<K, V>): Boolean {
return size > maxSize
}
}
fun <T, R> ((T) -> R).memoizeIdentity(maxCacheSize: Int): (T) -> R {
val memoized = { it: IdentityCharacteristics<T> ->
this(it.value)
}.memoize(maxCacheSize)
return { memoized(IdentityCharacteristics(it)) }
}
@PublishedApi
internal val SENTINEL_NULL = java.lang.Object()
/**
* Requires the map to only contain values of type [R] or [SENTINEL_NULL]. This is ensured if the map is only ever
* accessed via this function.
*/
inline fun <T, R> MutableMap<T, Any>.computeNullableFunction(key: T, crossinline func: () -> R): R {
val value = this.getOrPut(key) {
func() ?: SENTINEL_NULL
}
@Suppress("UNCHECKED_CAST")
return if (value === SENTINEL_NULL) null as R
else value as R
}
fun <T, R> ((T) -> R).memoize(maxCacheSize: Int): (T) -> R {
val map = mutableMapWithMaxSize<T, Any>(maxCacheSize)
return {
map.computeNullableFunction(it) { this@memoize(it) }
}
}
|
