came across a code like this today:
(0, eval)( "1+1" ); //2so 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?
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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