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This is a playground to test code. It runs a full Node.js environment and already has all of npm’s 1,000,000+ packages pre-installed, including @extra-set/count-as. Try it out:
const set = require("extra-set");
var x = new Set([1, 2, 3, 4, 5]);
set.countAs(x, v => v % 3);
set.countAs(x, v => v % 2);
- all documents on RunKit are public
require()any package directly from npm- use arrow functions, classes, template strings, and most of ES6
awaitany promise instead of using callbacks (example)- create your own embedded node.js snippets
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