Check if a datum exists without reading its value.
npm install level-existsCheck if a datum exists without reading its value.
``js
var exists = require('level-exists');
var level = require('level');
var db = level(__dirname + '/db');
exists.install(db);
db.del('foo', function(err) {
if (err) throw err;
db.exists('foo', function(err, yes) {
if (err) throw err;
console.log('foo exists? %s', yes);
// foo exists? false
db.put('foo', 'bar', function(err) {
if (err) throw err;
exists(db, 'foo', function(err, yes) {
if (err) throw err;
console.log('foo exists? %s', yes);
// foo exists? true
});
});
});
});
`
Check if there's a datum in db with key and call cb with (err, exists).
Install level-exists onto the db.
With npm do:
`bash``
npm install level-exists
(MIT)
Copyright (c) 2013 Julian Gruber <julian@juliangruber.com>
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