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Try any Node.js package right in your browser
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-map/concat-update. Try it out:
const map = require("extra-map");
var x = new Map([["a", 1], ["b", 2]]);
var y = new Map([["c", 3], ["d", 4]]);
map.concat$(x, y);
x;
var x = new Map([["a", 1], ["b", 2]]);
var z = new Map([["d", 40], ["e", 50]]);
map.concat$(x, y, z);
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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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