Always positive
It's need extra effort to understanding logic in negative condition, avoid it as you can
// ❌ Don't function isUserNotVerified(){ } if(!userVerified){ } // ✅ Do function isUserVerified(){ } if(userVerified){ } Use Shorthands if possible
Shorthands make your code use less line and easier to read
// ❌ Don't if(isActive ==null){ } if(firstname !== null || firstname !=='' || firstname !== undefined){ } const isUserValid = user.isVerified() && user.isActive() ? true : false; // ✅ Do if(isActive) { } if(!!firstname){ } const isUserValid = user.isVerified() && user.isActive() Object literals over Switch statements
// ❌ Don't const getStatus = (status) => { switch (status) { case "success": return "green"; case "failure": return "red"; case "warning": return "yellow"; case "loading": default: return "blue"; } }; // ✅ Do const statusColors = { success: "green", failure: "red", warning: "yellow", loading: "blue", }; const getStatus = (status) => statusColors[status] || statusColors.loading; Use optional chaining
Remember that optional chaining is not working with IE browser yet, see here
const alice = { name:'Alice', cat:{ name:'Nala' } } // ❌ Don't const cat = (alice && alice.cat && alice.cat.name) || 'N/A'; // ✅ Do const cat = alice?.cat?.name ?? 'N/A'; 
Top comments (3)
For shorthands like if(!!something), why cant we just do if (something)???
Yes you could, the only difference is !!something will return boolean