Optimization of fixed result functions generated in JS

Applicable functions must meet the following conditions:

Produce fixed results

Multiple calls on the page

Complex or time-consuming

The code and analysis are as follows:

Java code:

// Function that generates fixed results and is called multiple times on the page

Function check (){

// Simulate time-consuming operations

Var begin = Date. now (); // added by ECMAScript5. If not, change it to + new Date ();

Var ONE_SECOND = 1000,

Result = false;

While (true ){

If (Date. now ()-begin> = ONE_SECOND ){

Result = true;

Break;

}

}

// Rewrite the function and return the result directly.

Check = function (){

Return result;

}

Return result;

}

Var firstBegin = Date. now ();

Check (); // call the nth Function

Var firstEnd = Date. now ();

Check (); // second-level function call

Var secondEnd = Date. now ();

Console. log ("Time consumed by the nth function:" + (firstEnd-firstBegin) + "ms .");

Console. log ("second quadratic function time-consuming:" + (secondEnd-firstEnd) + "ms .");

The result is as follows: