Mastering JavaScript

Chapter 1
// GOOD
if ( foo ) ...
// When checking if a reference is false,
// BAD:
if ( foo === false ) ...
// GOOD
if ( !foo ) ...
// this will also match: 0, "", null, undefined, NaN
// If you MUST test for a boolean false, then use
if ( foo === false ) ...
// a reference that might be null or undefined, but NOT false, "" or
0,
// BAD:
if ( foo === null || foo === undefined ) ...
// GOOD
if ( foo == null ) ...
// Don't complicate matters
return x === 0 ? 'sunday' : x === 1 ? 'Monday' : 'Tuesday';
// Better:
if (x === 0) {
return 'Sunday';
} else if (x === 1) {
return 'Monday';
} else {
return 'Tuesday';
}
// Even Better:
switch (x) {
case 0:
return 'Sunday';
case 1:
return 'Monday';
default:
return 'Tuesday';
}
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