diff --git a/README.md b/README.md index 8010727..c32000d 100644 --- a/README.md +++ b/README.md @@ -3,11 +3,25 @@ jsonStorage A light abstraction for DOMStorage (such as localStorage). +Installation +=== + +Ender.JS (Browser) + + ender build json-storage + +Node.JS (Server) + + npm install localStorage json-storage + +Usage +=== + Made fo for Node.JS and Ender.JS (browser-side). var localStorage = require('localStorage') , JsonStorage = require('json-storage') - , db = JsonStorage(localStorage) + , db = JsonStorage(localStorage, 'my-app-prefix') , myValue = { foo: "bar" , baz: "quux" @@ -20,6 +34,7 @@ Made fo for Node.JS and Ender.JS (browser-side). API === + * JsonStorage(DOMStorage, 'application-prefix') // optional prefix * get(key) * set(key, value) * remove(key) @@ -30,12 +45,29 @@ API null vs undefined in JSON === -Since it is not valid to set `undefined` in JSON, calling `db.set('x')` is the same as `db.remove('x')`. +These notes do not reflect a bugs or defects in this library, +they're simply to inform you of a few 'gotchas' inherent in JSON / DOMStorage conversion. -However, `null`, and `"null"` both parse as `null` the "object", but the string (which would be `"\"null\""`). +99.999% of the time these gotchas shouldn't effect you in any way. +If they do, you're probably doing something wrong in the first place. -Therefore, setting a key to `undefined` will remove it from the db, but setting it to `null` will save it. -Yet both values that exist as `null` and values that don't exist will return `null`. +It is not valid to set `undefined` in JSON. So setting a key to `undefined` will remove it from the db. -Also `{ "foo": null, "bar": "null" }` will parse as `foo` being `null` but `bar` being `"null"`, much unlike the value `"null"` being parsed on its own. +This means that `db.set('x')` is the same as `db.remove('x')`. + +To save `undefined`, use `null` instead. + + +Note that both values that exist as `null` and values that don't exist at all will return `null`. + + db.set('existing-key', null); + null === db.get('existing-key'); + null === db.get('non-existant-key'); + + +The special case of `null` as `"null"`, aka `"\"null\""`: + +`null`, and `"null"` both parse as `null` the "object", instead of one being the string (which would be `"\"null\""`). + +Objects containing `null`, however, parse as expected `{ "foo": null, "bar": "null" }` will parse as `foo` being `null` but `bar` being `"null"`, much unlike the value `"null"` being parsed on its own. \ No newline at end of file