{ // start block statement a: // labeled statement [1] 1 // expression statement } // end block statement [ // start array literal “a

{ // start block statement a: // labeled statement [1] 1 // expression statement } // end block statement [ // start array literal “a” // string value ] // end array literal vs. ( // start expression statement { // start object literal a: // object literal key 1 // expression statement } // end object literal statement [ // begin subscript property access “a” // string (property key) ] // end subscript property access ) // end expression [1]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/label https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe... versus Edit: fixed second example (it did not match the parent comment), changed some verbiage