Write a rating component on a single line

Define a variable score with a value from 1 to 5, then execute the code above and look at the graph

"★★★★★ ★★★★★ ★★★★★ ★★★★★ ★★ ".Copy the code

What plug-ins are so weak compared to this!

JavaScript errors are handled in the correct manner

try {
    something
} catch (e) {
    window.location.href =
 "http://stackoverflow.com/search?q=[js]+" +
        e.message;
}
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Anonymous functions execute themselves

Which of these would you choose? I choose to die.

( function() {}() );
( function() {} )();
[ function() {}() ];

~ function() {}();
! function() {}();
+ function() {}();
- function() {}();

delete function() {}();
typeof function() {}();
void function() {}();
new function() {}();
new function() {};

const f = function() {}();

1, function() {}();
1 ^ function() {}();
1 > function() {}();
// ...
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Another kind of undefined

You never need to declare a variable to be undefined because JavaScript automatically sets an unassigned variable to undefined. So if you write that in code, you’ll be despised

const data = undefined;
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But if you are obsessive-compulsive, be sure to declare a variable that has no value for the time being and assign undefined. Here’s what you might consider:

const data = void 0; // undefined
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On how to gracefully round

Const = const ~ ~ 2.33 b = 2.33 | 0 const c = 2.33 > > 0Copy the code

How to gracefully implement money formatting: 1234567890 –> 1,234,567,890

Implement with regulars

const test1 = '1234567890' const format = test1.replace(/\B(? =(\d{3})+(? ! \d))/g, ',') console.log(format) // 1,234,567,890Copy the code

An elegant implementation of irregularity:

function formatCash(str) { return str.split('').reverse().reduce((prev, next, index) => { return ((index % 3) ? Next: (next + ',')) + prev})} console.log(formatCash('1234567890')) // 1,234,567,890Copy the code