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diff --git a/deps/npm/node_modules/pacote/node_modules/lru-cache/README.md b/deps/npm/node_modules/pacote/node_modules/lru-cache/README.md new file mode 100644 index 0000000000..435dfebb7e --- /dev/null +++ b/deps/npm/node_modules/pacote/node_modules/lru-cache/README.md @@ -0,0 +1,166 @@ +# lru cache + +A cache object that deletes the least-recently-used items. + +[](https://travis-ci.org/isaacs/node-lru-cache) [](https://coveralls.io/github/isaacs/node-lru-cache) + +## Installation: + +```javascript +npm install lru-cache --save +``` + +## Usage: + +```javascript +var LRU = require("lru-cache") + , options = { max: 500 + , length: function (n, key) { return n * 2 + key.length } + , dispose: function (key, n) { n.close() } + , maxAge: 1000 * 60 * 60 } + , cache = new LRU(options) + , otherCache = new LRU(50) // sets just the max size + +cache.set("key", "value") +cache.get("key") // "value" + +// non-string keys ARE fully supported +// but note that it must be THE SAME object, not +// just a JSON-equivalent object. +var someObject = { a: 1 } +cache.set(someObject, 'a value') +// Object keys are not toString()-ed +cache.set('[object Object]', 'a different value') +assert.equal(cache.get(someObject), 'a value') +// A similar object with same keys/values won't work, +// because it's a different object identity +assert.equal(cache.get({ a: 1 }), undefined) + +cache.reset() // empty the cache +``` + +If you put more stuff in it, then items will fall out. + +If you try to put an oversized thing in it, then it'll fall out right +away. + +## Options + +* `max` The maximum size of the cache, checked by applying the length + function to all values in the cache. Not setting this is kind of + silly, since that's the whole purpose of this lib, but it defaults + to `Infinity`. Setting it to a non-number or negative number will + throw a `TypeError`. Setting it to 0 makes it be `Infinity`. +* `maxAge` Maximum age in ms. Items are not pro-actively pruned out + as they age, but if you try to get an item that is too old, it'll + drop it and return undefined instead of giving it to you. + Setting this to a negative value will make everything seem old! + Setting it to a non-number will throw a `TypeError`. +* `length` Function that is used to calculate the length of stored + items. If you're storing strings or buffers, then you probably want + to do something like `function(n, key){return n.length}`. The default is + `function(){return 1}`, which is fine if you want to store `max` + like-sized things. The item is passed as the first argument, and + the key is passed as the second argumnet. +* `dispose` Function that is called on items when they are dropped + from the cache. This can be handy if you want to close file + descriptors or do other cleanup tasks when items are no longer + accessible. Called with `key, value`. It's called *before* + actually removing the item from the internal cache, so if you want + to immediately put it back in, you'll have to do that in a + `nextTick` or `setTimeout` callback or it won't do anything. +* `stale` By default, if you set a `maxAge`, it'll only actually pull + stale items out of the cache when you `get(key)`. (That is, it's + not pre-emptively doing a `setTimeout` or anything.) If you set + `stale:true`, it'll return the stale value before deleting it. If + you don't set this, then it'll return `undefined` when you try to + get a stale entry, as if it had already been deleted. +* `noDisposeOnSet` By default, if you set a `dispose()` method, then + it'll be called whenever a `set()` operation overwrites an existing + key. If you set this option, `dispose()` will only be called when a + key falls out of the cache, not when it is overwritten. +* `updateAgeOnGet` When using time-expiring entries with `maxAge`, + setting this to `true` will make each item's effective time update + to the current time whenever it is retrieved from cache, causing it + to not expire. (It can still fall out of cache based on recency of + use, of course.) + +## API + +* `set(key, value, maxAge)` +* `get(key) => value` + + Both of these will update the "recently used"-ness of the key. + They do what you think. `maxAge` is optional and overrides the + cache `maxAge` option if provided. + + If the key is not found, `get()` will return `undefined`. + + The key and val can be any value. + +* `peek(key)` + + Returns the key value (or `undefined` if not found) without + updating the "recently used"-ness of the key. + + (If you find yourself using this a lot, you *might* be using the + wrong sort of data structure, but there are some use cases where + it's handy.) + +* `del(key)` + + Deletes a key out of the cache. + +* `reset()` + + Clear the cache entirely, throwing away all values. + +* `has(key)` + + Check if a key is in the cache, without updating the recent-ness + or deleting it for being stale. + +* `forEach(function(value,key,cache), [thisp])` + + Just like `Array.prototype.forEach`. Iterates over all the keys + in the cache, in order of recent-ness. (Ie, more recently used + items are iterated over first.) + +* `rforEach(function(value,key,cache), [thisp])` + + The same as `cache.forEach(...)` but items are iterated over in + reverse order. (ie, less recently used items are iterated over + first.) + +* `keys()` + + Return an array of the keys in the cache. + +* `values()` + + Return an array of the values in the cache. + +* `length` + + Return total length of objects in cache taking into account + `length` options function. + +* `itemCount` + + Return total quantity of objects currently in cache. Note, that + `stale` (see options) items are returned as part of this item + count. + +* `dump()` + + Return an array of the cache entries ready for serialization and usage + with 'destinationCache.load(arr)`. + +* `load(cacheEntriesArray)` + + Loads another cache entries array, obtained with `sourceCache.dump()`, + into the cache. The destination cache is reset before loading new entries + +* `prune()` + + Manually iterates over the entire cache proactively pruning old entries |