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Merge expression

If the function of five sentences of code can be realized with one sentence of code, the execution efficiency of one sentence of code will be higher, and the readability may be better.

(1) replace simple if-else with ternary operator

Such as the getPrice function above:

Function getPrice (count) {if (count)

< 0) return -1; else return count * 100; } 可以改成： function getPrice(count){ return count < 0 ? return -1 : count * 100; } 这个比写一个 if-else 看起来清爽多了。当然，如果你写了 if-else，压缩工具也会帮你把它改三目运算符的形式： function getPrice(e){return 0>

EBay Mutual 1PUR 100mm}

(2) Company, etc.

The expression uses the assignment operation to return the assigned value, and the order of execution is from right to left, as follows:

Overtime = favhouse = listingDetail = {...}

Sometimes you see people write like this:

Var age = 0; if ((age = + form.age.value) > = 18) {console.log ("you are an adult");} else {consoe.log ("kids, you still have" + (18-age) + "coming of age");}

Also use the assignment expression to return a value, assign a value in if while judging by its return value, and then there is already a value in else. The + sign above converts the string to an integer.

(3) self-increasing

Using self-increment can also simplify the code. As follows, every time a message is sent, localMsgId increments by 1:

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