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The correct answer is (C) XMLLIST()

For EXPLANATION: An XML fragment is an XML DOCUMENT with no single top-level root ELEMENT. When working with XML fragments, use XMLList() instead of XML().

The correct option is (a) ..

Easy explanation: While the . OPERATOR ACCESSES direct children of the given node, the .. operator accesses all children no matter how DEEPLY nested: The .. operator is the DESCENDANT operator; you can use it in place of the normal. member-access operator:

Correct answer is (d) After try-catch execution

To explain: The try and catch STATEMENT HANDLES some or all of the errors that may occur in a block of code, while STILL RUNNING code. A finally block is CALLED after try-catch execution.

Correct option is (C) Takes it to be TRUE

The explanation: The try and catch statement handles some or all of the errors that may occur in a block of code, while STILL running code. If a catch clause has no conditional, it BEHAVES as if it has the conditional if true, and it is always triggered if no clause before it was triggered.

Right option is (b) object

To explain I would say: The TYPEOF operator returns “object” for all standard JAVASCRIPT OBJECTS. It returns “object” for a null, “number” for NaN, “number” for Infinity, “object” for a “new Number(1)” and “object” for an array.

The correct answer is (d) Stop ITERATION

The best explanation: Iterators that work on finite COLLECTIONS throw Stop Iteration from their next() method when there are no more values to iterate. Stop Iteration is a property of the global object in JavaScript 1.7. Its value is an ordinary object (with no PROPERTIES of its own) that is reserved for this special purpose of TERMINATING iterations. Note, in PARTICULAR,that Stop Iteration is not a constructor function like TypeError() or RangeError().

The correct OPTION is (a) let trimmed = (l.TRIM() for (l in lines));

Best EXPLANATION: The various types of trim functions are trimLeft(), trimRight() and trim().can use the above code to trim whitespaces and FILTER out comments and blank lines.

The correct answer is (c) for/each loop

Easy explanation: The for/each loop is a NEW LOOPING statement STANDARDIZED by E4X. E4X (ECMASCRIPT for XML) is a language extension that allows XML tags to appear literally in JavaScript programs and adds syntax and API for OPERATING on XML data.

Right choice is (b) let is CONFINED to a particular function but var is not

Best explanation: Variables declared with var have global scope whereas VARIABLE declared with let have BLOCK scope. Variables declared with let are DEFINED only within the CLOSEST enclosing block (and any blocks nested within it, of course).

Right option is (d) in a else if LOOP, as a substitute for var

The explanation is: The LET keyword can be used in FOUR ways :

as a VARIABLE declaration like var;

in a for or for/in loop, as a substitute for var;

as a block statement, to define new variables and explicitly delimit their scope; and

to define variables that are scoped to a single EXPRESSION.

Correct option is (d) ADSafe

The explanation is: ADsafe was one of the FIRST security SUBSETS PROPOSED) It was created by Douglas Crockford (who also defined The Good Parts subset). ADsafe relies on static verification only, and it uses JSLint as its verifier. It forbids access to most GLOBAL variables and defines an ADSAFE variable that provides access to a secure API, including special-purpose DOM methods. ADsafe is not in WIDE use, but it was an influential proof-of-concept that influenced other secure subsets.

Right answer is (b) eval() and the FUNCTION() constructor

To explain: eval() and the Function() constructor are not ALLOWED in any SECURE subset because they allow the execution of arbitrary strings of code, and these strings cannot be STATICALLY ANALYZED.

The correct CHOICE is (d) To improve programmer productivity

To explain I would say: The Good Parts is a language subset designed for aesthetic reasons and with a desire to improve programmer productivity. There is a larger class of subsets that have been designed for the purpose of SAFELY running UNTRUSTED JavaScript in a secure container or “SANDBOX”.

Correct choice is (a) SANDBOX

Easy EXPLANATION: There is a larger class of SUBSETS that have been designed for the purpose of safely RUNNING untrusted JavaScript in a secure container or “sandbox”.

Right OPTION is (c) A static verifier that parses code

Best explanation: Each SUBSET is COUPLED with a static verifier that parses code to ENSURE that it CONFORMS to the subset.

Correct CHOICE is (d) replace()

The best I can explain: The replace() method PERFORMS a search-and-replace operation. It takes a REGULAR EXPRESSION as its first argument and a replacement STRING as its second argument.

The correct option is (b) Define subpatterns within the COMPLETE pattern

The BEST explanation: When a REGULAR expression is successfully matched against a target STRING, it is possible to extract the portions of the target string that matched any particular paranthesized subpattern. The essential PURPOSE of parantheses in regular expressions is to define subpatterns within the complete pattern.

Right CHOICE is (a) It matches “java” followed by the optional “SCRIPT”

For explanation: PARANTHESIS () CHECK for the optional presence of the argument in the STRING. subexpression /java(script)?/ matches “java” followed by the optional “script”.

The correct option is (a) Matches the LETTER b preceded by the fewest number of a’s possible

The best explanation: Using NON greedy repetition may not always produce the RESULTS you expect. /a+?b/ matches the letter b preceded by the fewest number of a’s possible.

Correct choice is (c) Match zero or more characters that are not OPEN parenthesis

To EXPLAIN I would SAY: The [^…] character class is used to match or draw any one character not between the brackets. One should always be careful while using * and ? as REPETITION characters as they may match zero INSTANCES of whatever precedes them, they are allowed to match nothing.

The correct ANSWER is (C) [^…]

For explanation I would SAY: RegExp DEFINES a special set of character that is used to do MANIPULATION on strings and other variables. The [^…] character class is used to match or draw any one character not between the brackets.

Correct choice is (a) Register the MODULE’s API and Store their API

Explanation: FRAMEWORKS that DEFINE module loading systems MAY have other methods of exporting a module’s API. There may be a provides() function for MODULES to register their API, or an exports object into which modules must store their API.

The correct answer is (C) metacharacter

Easiest explanation: The ‘S’ is a special metacharacter that MATCHES the end of a STRING. It is used to define or access ELEMENTS in jquery.

The correct answer is (b) Non-enumerable method

To explain: The PROPERTIES() is a method to get INFORMATION of the properties of a PARTICULAR object. properties() method is a non-enumerable method.

The correct answer is (c) RETURN a namespace object

The explanation is: Namespace is a container for a set of identifiers, FUNCTIONS, methods and all that. It GIVES a level of DIRECTION to its contents so that it will be well distinguished and organized. Modules that have more than one item in their API can return a namespace object.

Correct answer is (b) MODULE function

To ELABORATE: The SCOPE of a function can be used as a PRIVATE NAMESPACE for a module. Therefore, the scope of a function is called a module function.

The correct answer is (b) sets.SingletonSet = sets.AbstractEnumerableSet.EXTEND(…);

To explain I would SAY: Singleton is an object which can only be instantiated once. The extend keyword is used in class declarations or class expressions to create a class which is a CHILD of another class. The sets object is the namespace for the module, and we define each of the set classes as a property of this object.

Correct OPTION is (C) 1

For explanation: GENERALLY, the various modules are allowed to run in the pristine (or near pristine) ENVIRONMENT that it expects. The modules should minimize the number of global symbols they define – ideally, no MODULE should define more than one.

The CORRECT answer is (b) HTMLElement.prototype

To explain I would say: It is implementation-dependent whether classes defined by the host environment (such as the web browser) can be augmented using Object.prototype. In MANY web browsers, for example, you can add methods to HTMLElement.prototype and those methods will be inherited by the OBJECTS that represent the HTML tags in the CURRENT document.

Correct option is (a) declaring and loading modules

To explain I would SAY: Both the Dojo toolkit and GOOGLE’s Closure library DEFINE PROVIDE() and require() FUNCTIONS for declaring and loading modules.

The correct answer is (a) Complex.prototype.conj = FUNCTION() { RETURN new Complex(this.r, -this.i); };

Explanation: OBJECT.prototype.constructor specifies the function that CREATES the object prototype. The above code snippet returns a complex number that is the complex CONJUGATE of this one.

Right ANSWER is (b) ii, III and iv only

The best explanation: Date() is a PREDEFINED object type in javascript. There are 4 ways to create a new date object:new Date(), new Date(year, month, day, HOURS, MINUTES, seconds, milliseconds), new Date(milliseconds), new Date(date string).

Correct choice is (b) VARIABLE PROPERTIES

The explanation is: The variable properties are usually VARIABLES that are used INTERNALLY in the object’s methods, but can also be globally visible variables that are used through the page.

Correct option is (C) Constructor object, Prototype object, INSTANCE object

Easiest explanation: In JavaScript, there are three different objects involved in any class definition, and the properties of these three objects act like different kinds of class members namely, Constructor object, Prototype object, and Instance object.

The correct ANSWER is (c) B.PROTOTYPE=INHERIT(A);

The explanation: inherit() function is a predefined function in javascript which is used to inherit properties of another class. The subclass B inherits the prototype of the class A.

Right choice is (b) INSTANCE fields, Instance methods, Class fields, Class methods

Explanation: A class mainly contains DATA members and associated member FUNCTIONS. Therefore over all DIFFERENT KINDS of class members are instance field, instance method, class fields and class methods.

The correct answer is (a) var t=new FilteredSet(s, {function(s) {return !(X INSTANCEOF Set);});

Best explanation: The instanceof operator is used to check the type of an object at run TIME. The instanceof operator returns a boolean VALUE that indicates if an object is an instance of a particular class.

The correct ANSWER is (a) A is the SUPERCLASS and B is the SUBCLASS

For EXPLANATION: Superclass is the class from which subclasses are defined. Subclasses are also called EXTENSIONS of superclass.therefore in the above scenario A will be superclass and B will be subclass.

The correct choice is (c) it is INVOKED automatically by the JSON.stringify() method

Explanation: A common use of JSON is to exchange DATA to/from a web server. When sending data to a web server, the data has to be a STRING. In that CASE json.strigify() is used to CONVERT a javascript object into a string.

The CORRECT choice is (a) objects inherit prototype properties even in a dynamic state

To EXPLAIN: JavaScript’s prototype-based inheritance mechanism is dynamic an object inherits properties from its prototype, even if the prototype CHANGES after the object is created. This means that we can augment JavaScript CLASSES simply by adding NEW methods to their prototype objects.

The correct answer is (d) Functions are values, and there is no hard DISTINCTION between methods and fields

Easiest explanation: JAVA is an OOP programming language while JavaScript is an OOP scripting language. The BASIC DIFFERENCE between JavaScript and Java is that the functions are values, and there is no hard distinction between methods and fields.