[JavaScript] ecmascript 6 spread

Recently, when implementing a class method, the younger brother must pass parameters to ensure that the new keyword is not used to generate strength. So it took a lot of effort,CodeStill not beautiful enough. Finally, the answer is es6's spread.

 

See https://github.com/Neverland/Class/blob/master/script/class.js for details

 

Es6 official explanation of SPRED is:

• Replace an array or array-like actual parameter value with its elements as positional parameters
• LetNewCompose withThis-Free FormApply
• Remove (some day, and in similar future methods) automagic (and half-the-time wrong) array flattening, e.g. InArray. Prototype. Concat 

As follows

1. Replace the actual parameter values such as arrays or arrays with multiple positional parameters.

2. You do not need to consider using apply when using new.

3. Remove automated array flattening

 

Syntax:

... Very simple.

 

Case study:

1. If both new and apply are used, the syntax will be incorrect. // new elements. Apply (document. getelementsbytagname ('div '));

 

 
NewElements(...doc ument. getelementsbytagname ('div '));
 

 

2. Structure assignment, which can be split into segments

 
VaR [A,... B] = [1, 2, 3, 4];
A // 1;
B // [2, 3, 4]
 

 

3. Directly disassemble class arrays or array parameters when calling a function

VaR A = [1, 2, 4];

If array a is split into four values when a function is called

 
Add. Apply (this, );
 

Now

 
Add (... );