(0, eval) ("1mm 1") A passing Daniel will explain why this line of code can be written in this way. What do you mean?

came across a code like this today: 

(0, eval)( "1+1" );    //2

so I copied one: 

( 0, function( a ) {
    console.log( a );        //"hello world"
} )( "hello world" );

( function( a ) {
    console.log( a );        //
}, function( b ) {
    console.log( b );        //"hello world"
} )( "hello world" );

instant? Fly by, which god can explain?

Javascript
May.03,2021

you have to understand what a comma means
https://developer.mozilla.org.
is the last to be valid

1. One of the uses of parentheses is to execute one or more expressions and return the value of the last expression, which requires a comma between multiple expressions. "separate
example: (1 code >) / / the code is executed at once, and finally 6 is used as the return value
2. Execute the anonymous function (function () {}) ()
, so you can think of this as equal to (eval) ('1cm 1')
again equal to eval (' 1th 1')

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