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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 @nathanfaucett/weak_map_polyfill. Try it out:
var weakMapPolyfill = require("@nathanfaucett/weak_map_polyfill")
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awaitany promise instead of using callbacks (example)- create your own embedded node.js snippets
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