nl_tokens: Assigns value to key of object if the existing value is not equivalent using [ SameValueZero ] ( http : // ecma - international . org / ecma - 262 / 7 . 0 / #sec - samevaluezero ) for equality comparisons .
pl_tokens: function assignValue ( object , <mask> , value ) { var objValue = object [ key ] ; if ( ! ( hasOwnProperty$3 . call ( object , key ) && eq$2 ( objValue , value ) ) || ( value === undefined && ! ( key in object ) ) ) { object [ key ] = value ; } }