he/him 
Why do people worry so much about function allocations but don’t worry about dynamic dispatch? There are so many pattern where this.something causes deopts, especially if you compile classes and class properties with Babel.
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If you look at function() {} and think “oh this must be expensive”, and then look at http://this.foo and think “accessing this is free” you might want to check your guesses. (In a real app, not a benchmark — benchmarks don’t represent what happens with real components.)
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Real-world example: I made the Babel parser 25% faster by converting a deep Parser class hierarchy to functions. Caused the engine to inline more and didn't need expensive dynamic dispatchhttps://twitter.com/sebmck/status/951299423622975489 …
