Parallelism and Symmetry

Like in writing, parallelism and symmetry can make your coding effective, classy, and certain to impress anyone who reads it.

Transcript

1. Parallelism and Symmetry Alex Tercete @alextercete
4. Writing
5. Verb forms
6. Olympic athletes usually like practicing, competing, and to eat ice cream sandwiches. DON'T Alice Underwood @ Grammarly <https://www.grammarly.com/blog/parallelism/>
7. Olympic athletes usually like practicing, competing, and eating ice cream sandwiches. or Olympic athletes usually like to practice, compete, and eat ice cream sandwiches. DO Alice Underwood @ Grammarly <https://www.grammarly.com/blog/parallelism/>
8. Nouns vs. verbs
9. For dinner we like lamb chops and to fry brussel sprouts. DON'T Alice Underwood @ Grammarly <https://www.grammarly.com/blog/parallelism/>
10. For dinner we like lamb chops and brussel sprouts. or For dinner we like to grill lamb chops and fry brussel sprouts. DO Alice Underwood @ Grammarly <https://www.grammarly.com/blog/parallelism/>
11. Noun number
12. Public transit such as buses or a train can help reduce air pollution. DON'T Alice Underwood @ Grammarly <https://www.grammarly.com/blog/parallelism/>
13. Public transit such as buses or trains can help reduce air pollution. DO Alice Underwood @ Grammarly <https://www.grammarly.com/blog/parallelism/>
14. Coding
15. Collections
16. DON'T function getThings(): Thing[] { const things = getFirstHalfOfThings(); things.push(...getSecondHalfOfThings()); return things; }
17. DON'T function getThings(): Thing[] { const things = getFirstHalfOfThings(); const secondHalfOfThings = getSecondHalfOfThings(); things.push(...secondHalfOfThings); return things; }
18. DON'T function getThings(): Thing[] { const things = getFirstHalfOfThings(); const secondHalfOfThings = getSecondHalfOfThings(); return things.concat(secondHalfOfThings); }
19. DO function getThings(): Thing[] { const things: Thing[] = []; things.push(...getFirstHalfOfThings()); things.push(...getSecondHalfOfThings()); return things; }
20. DO function getThings(): Thing[] { const firstHalf = getFirstHalfOfThings(); const secondHalf = getSecondHalfOfThings(); return firstHalf.concat(secondHalf); }
21. DO function getThings(): Thing[] { const firstHalf = getFirstHalfOfThings(); const secondHalf = getSecondHalfOfThings(); return [...firstHalf, ...secondHalf]; }
22. Chains
23. DON'T function getStuffName(): Promise<Stuff> { return fetchThing().then(convertToStuff) .then(stuff => stuff.name); }
24. DO function getStuffName(): Promise<Stuff> { return fetchThing() .then(convertToStuff) .then(stuff => stuff.name); }
25. DO function getStuffName(): Promise<Stuff> { return fetchThing() .then(thing => convertToStuff(thing)) .then(stuff => stuff.name); }
26. DO function getStuffName(): Promise<Stuff> { return fetchThing() .then(thing => convertToStuff(thing)) .then(stuff => getName(stuff)); }
27. DO function getStuffName(): Promise<Stuff> { return fetchThing() .then(convertToStuff) .then(getName); }
28. Exports
29. const thing = createThing(); export default thing;
30. DON'T const thing = createThing(); export const thingWithSomething = createThingWithSomething(); export default thing;
31. DON'T export default const thing = createThing(); // Doesn't compile export const thingWithSomething = createThingWithSomething();
32. DO const thing = createThing(); const thingWithSomething = createThingWithSomething(); export default thing; export { thingWithSomething };
33. DO const thing = createThing(); const thingWithSomething = createThingWithSomething(); export { thing as default, thingWithSomething };
34. Thomas Hawk <https://www.flickr.com/photos/thomashawk/15916803197/>