Javascript Assessment Test

Javascript Assessment Test

PorEdward Yao

Es posible que este libro digital no cumpla las normas de accesibilidad y no sea totalmente compatible con las tecnologías de asistencia.
How well do you know the Javascript language? Take the JSAT and find out. The Javascript Assessment Test (85 questions) Time limit: 45 minutes (All answers found at end of book) Select the best answer for each question. 1. The statement below creates a new context. eval?.("'use strict'; function f(){console.log('hello')}") a. true b. false 2. Under non-strict mode, a statement x = 40 performs what action? a. variable declaration b. variable assignment c. variable declaration or assignment d. variable declaration and assignment e. none of the above 3. What best describes the type of relationship between the variable named i and the anonymous function in the code below: var a = []; for (var i=0; i<5; ++i){ a[i] = function(){ console.log(i); } } a. one-to-one b. one-to-many c. many-to-one d. many-to-many e. none of the above 4. Which of the options below would solve the script error? function f(){ this.msg = "hello" } f.prototype.greet = function(name){ console.log(`${this.msg}, ${name}`) } } const obj = new f() setTimeout(obj.greet, 1000, "world!") a. iteration or recursion b. block or constant variable c. function wrapper or reference d. call or apply method e. none of the above 5. The var keyword creates properties on the window object. a. true b. false 6. Every object instance has a prototype property. a. true b. false 7. The strict mode is automatically in effect for a given script. a. true b. false 8. Using the let keyword creates properties on the global object. a. true b. false 9. How many closures or contexts are created in the given script? var list = []; f(); list.forEach(fn=>fn()); function f(){ var strings = ["romeo", "sierra", "tango"]; for (let i = 0; i < 3; i++){ list[i] = ()=>console.log(list[i], strings[i]); } } a. 5 b. 9 c. 11 d. 7 e. none of the above 10. Every object instance has a __prototype__ property. a. true b. false 11. The formal argument of the given dynamic function forms a closure with the custom Date() function. (function(){ function Date(){ console.log(“Have a happy date!”); } new Function(“Date”, "return Date()")(Date); })(); a. true b. false 12. How many variables exist while the function f is running? var x = 0; var y = 1; function f() { var x = y; } f(); a. 2 b. 3 c. 5 d. 4 e. none of the above

Detalles

Fecha de publicación
Sep 18, 2022
Idioma
English
ISBN
9781387600755
Categoría
Computadoras y tecnología
Copyright
Todos los derechos reservados - Licencia estándar de copyright
Contribuyentes
Por (autor o autora): Edward Yao

Especificaciones

Formato
EPUB

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