Fighting Boolean Traps - Speaker Deck

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Fighting Boolean Traps

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Readable, consistent, crystal clear Thank you, Captain Obvious!

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https://twitter.com/AriyaHidayat/status/455892955765551105

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I HAVE A BAD FEELING ABOUT THIS…

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A long time ago in a galaxy far far away…

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var powerSlider = new Slider();

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var anotherSlider = new Slider(false);

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IT’S A TRAP!

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IT’S A BOOLEAN TRAP!

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s2 = new Slider(false); s1 = new Slider(true);

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s2 = new Slider(false /*horiz*/); s1 = new Slider(true /*vertical*/);

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Code is written once, read many times.

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s1 = new Slider({ orientation: "vertical" }); s2 = new Slider({ orientation: "horizontal" });

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s2 = new VerticalSlider(); s1 = new HorizontalSlider();

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contacts.find(str);

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// Check the cache first contacts.find(str, true); // Fresh search only contacts.find(str, false);

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IT’S A MODIFIER TRAP!

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the more the merrier

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Ping-pong, Anyone? // Expand + animate treeItem.setState(true, true); // Expand + don't animate treeItem.setState(true, false); // Collapse + animate treeItem.setState(false, true);

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DOM Event event.initKeyEvent("keypress", true, true, null, null, false, false, false, false, 9, 0);

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Double Negatives X.disabled = false; Y.setHidden(true); filter.caseInsensitive = true; X.enabled = true; Y.setVisible(false); filter.caseSensitive = false;

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picker.yearFrom = 1980; picker.yearTo = 2020; picker.minimumYear = 1980; picker.maximumYear = 2020;

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this.callMe = "Adam"; flight.from = SFO; flight.to = JFK; this.name = "Adam"; flight.departure = SFO; flight.destination = JFK;

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var x = Math.sqrt(-2) isNaN(x) true x === NaN false isNaN('hola') true x == NaN false

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https://twitter.com/AriyaHidayat/status/393034774245171200

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GarlicNaN != NaN Future JavaScript?

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Best Practices

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#1: Private by Default Public = Irreversible

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SHStripMneumonic “Why is the function SHStripMneumonic misspelled?” Raymond Chen, Microsoft http://blogs.msdn.com/b/oldnewthing/archive/2008/05/19/8518565.aspx

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-- yours truly “You’d fail your first two attempts anyway.”

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#2: Mandatory API Review

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“Write 3 examples which use the API.”

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#3: Build and Use TOOLS

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Summary

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Boolean traps (and other API mistakes) lead to FEAR

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[Yoda]

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Thank You Some artworks are from https://unsplash.com/ and http://openclipart.org. speakerdeck.com/ariya @ariyahidayat