This document provides an overview and explanation of React Hooks. It introduces common Hooks like useState, useEffect, useReducer, and custom hooks. useState is used to add local state to functional components. useEffect is similar to component lifecycle methods and lets you perform side effects. useReducer is an alternative to useState for managing state in a single object. Custom hooks let you extract reusable logic and share it without changing components. The document also includes a FAQ addressing questions about hooks and class components.
This document provides an overview of unit testing AngularJS applications using Karma, Jasmine, and Angular mocks. It discusses how to set up tests using Karma and Jasmine, write specs using matchers and spies, and mock dependencies using Angular mocks. Key points covered include isolating units of code for testing, using Karma to run tests in browsers, the structure of Jasmine specs, and mocking HTTP requests and other services.
React Hooks were introduced in React 16.8 to add state and side effects to function components by replacing class components. Common hooks include useState for managing component state, useEffect for handling side effects like data fetching, useCallback for creating memoized functions, and useRef for creating references that don't trigger re-renders when mutated. Hooks allow extracting logic into custom reusable hooks and following a few simple rules helps avoid bugs.
This document discusses React hooks and how they enhance functional components. It explains that hooks allow functional components to maintain state and lifecycle methods like class components. The key hooks discussed are useState for managing state, useEffect for side effects like data fetching, and useCallback and useMemo for optimization. Custom hooks are also covered as a way to extract reusable logic. Overall, hooks improve on class components by making code more modular, reusable and easier to test.
This document discusses the Jasmine framework for testing JavaScript code. It describes Jasmine as a behavior-driven development framework that does not depend on other frameworks. The key components of Jasmine include test suites defined with describe(), individual test specs defined with it(), and expectations defined with expect() and matchers. Suites, specs, and expectations are the main parts of writing Jasmine tests. The document also covers grouping tests, setup and teardown, pending and disabled tests, custom matchers, spies, and other Jasmine features.
This document provides an overview of various tools for testing AngularJS applications, including testing frameworks like Jasmine and Mocha, unit testing with Karma and ngMock, end-to-end testing with Protractor, and automating tasks with Grunt. It describes the purpose and basic usage of these tools, provides code examples, and lists additional resources for learning more.
This document discusses Angular JS unit testing and provides examples of testing controllers, routes, services, and directives. It introduces Karma and Jasmine, two popular tools for Angular testing. Karma is a test runner that executes unit tests. Jasmine is a BDD framework used for writing unit tests with matchers to make assertions. Examples are given for setting up tests for controllers, routes, services, and directives by injecting dependencies and compiling elements.
This document provides an overview and explanation of React Hooks. It introduces common Hooks like useState, useEffect, useReducer, and custom hooks. useState is used to add local state to functional components. useEffect is similar to component lifecycle methods and lets you perform side effects. useReducer is an alternative to useState for managing state in a single object. Custom hooks let you extract reusable logic and share it without changing components. The document also includes a FAQ addressing questions about hooks and class components.
This document provides an overview of unit testing AngularJS applications using Karma, Jasmine, and Angular mocks. It discusses how to set up tests using Karma and Jasmine, write specs using matchers and spies, and mock dependencies using Angular mocks. Key points covered include isolating units of code for testing, using Karma to run tests in browsers, the structure of Jasmine specs, and mocking HTTP requests and other services.
React Hooks were introduced in React 16.8 to add state and side effects to function components by replacing class components. Common hooks include useState for managing component state, useEffect for handling side effects like data fetching, useCallback for creating memoized functions, and useRef for creating references that don't trigger re-renders when mutated. Hooks allow extracting logic into custom reusable hooks and following a few simple rules helps avoid bugs.
This document discusses React hooks and how they enhance functional components. It explains that hooks allow functional components to maintain state and lifecycle methods like class components. The key hooks discussed are useState for managing state, useEffect for side effects like data fetching, and useCallback and useMemo for optimization. Custom hooks are also covered as a way to extract reusable logic. Overall, hooks improve on class components by making code more modular, reusable and easier to test.
This document discusses the Jasmine framework for testing JavaScript code. It describes Jasmine as a behavior-driven development framework that does not depend on other frameworks. The key components of Jasmine include test suites defined with describe(), individual test specs defined with it(), and expectations defined with expect() and matchers. Suites, specs, and expectations are the main parts of writing Jasmine tests. The document also covers grouping tests, setup and teardown, pending and disabled tests, custom matchers, spies, and other Jasmine features.
This document provides an overview of various tools for testing AngularJS applications, including testing frameworks like Jasmine and Mocha, unit testing with Karma and ngMock, end-to-end testing with Protractor, and automating tasks with Grunt. It describes the purpose and basic usage of these tools, provides code examples, and lists additional resources for learning more.
This document discusses Angular JS unit testing and provides examples of testing controllers, routes, services, and directives. It introduces Karma and Jasmine, two popular tools for Angular testing. Karma is a test runner that executes unit tests. Jasmine is a BDD framework used for writing unit tests with matchers to make assertions. Examples are given for setting up tests for controllers, routes, services, and directives by injecting dependencies and compiling elements.
React js use contexts and useContext hookPiyush Jamwal
The document discusses the useContext hook in React. It explains that hooks are special functions that start with "use" and are analogous to class component methods. The useContext hook allows components to access data from their parent context without having to pass props down through each level. Without useContext, data would need to be passed through props from the parent component to child components. With useContext, a Context Provider wraps components and provides a value that can be accessed using useContext in any child component without passing props.
This document discusses function parameters and how values are passed into functions in Python. It explains that parameters hold the values passed as arguments during a function call. Parameters act as variables inside the function that can be used, but changes to the parameter do not affect the original argument as Python passes arguments by value rather than by reference. The document provides examples of functions with single and multiple parameters as well as how to return multiple values from a function.
A step towards the way you write the code in React application.In this presentation, I have given introduction about React hooks. Why we need it in our react applications and describe about the two most commonly used React Hooks API useState and useEffect. I also given the links of code snippets I added in these slides
AngularJS Unit Testing w/Karma and Jasminefoxp2code
This document provides instructions for setting up Angular unit testing with Karma and Jasmine. It discusses initializing Karma and Jasmine via NPM, configuring Karma, adding Angular and Angular mocks via Bower, writing describe and it blocks for tests, and using matchers and mocks like $httpBackend. The live coding section at the end indicates the document will demonstrate these concepts in real tests.
The document discusses how to create a custom transformer in Mule by implementing the AbstractTransformer interface and overriding its methods. It provides an example of a KeyTransformer class that takes the source object, gets its string value, and prepends "Hello " to a substring. The document explains that this custom transformer can then be added via the Custom Transformer component in Mule to apply this transformation.
This lightning talk discusses replacing threads with actors for making concurrent service calls in web applications. It describes how actors provide an alternative concurrency model that can be more resource efficient than threads. The talk shows how to implement a master/worker pattern using Akka actors to dispatch work to remote services in parallel from a servlet, collecting the responses to render the page. Key advantages of the actor model include easier reasoning about concurrency and built-in supervision to restart failed actors.
Functions in programming have a definition including a return value, name, parameter list, and body of statements. To declare a function, the def keyword is used followed by the function name and parameters in parentheses. Functions are called by writing the function name followed by parentheses containing any parameters and can return a value.
Test-Driven Development of AngularJS ApplicationsFITC
The document discusses test driven development for AngularJS applications. It outlines problems with traditional front-end development approaches like jQuery manipulation and lack of structure/modularity. The solution presented uses Node.js, NPM, Bower, Grunt, Jasmine and other tools to automate tasks, add structure and enable testing. Features of an example task tracking app are developed using a test-first approach with end-to-end and unit tests. The app is built incrementally by splitting development into small features and writing tests for each.
The document discusses the Command design pattern, which encapsulates requests as objects so that different requests can be parameterized, queued, logged, or made undoable. The pattern addresses the need to issue requests without knowing the operation or receiver. A command defines an interface for executing an operation, concrete commands bind a receiver to an action, and a client creates concrete commands while an invoker carries out the request.
The return statement ends function execution and returns a value to the calling statement. It can return values from built-in functions or user-defined functions. Variables defined inside a function are local and hidden from other functions, while global variables defined outside functions can be accessed throughout the program. Local variables only exist during function execution and are destroyed afterward.
This document discusses AngularJS unit testing. It covers why unit testing is important, setting up a basic testing environment with tools like Karma and Jasmine, writing different types of tests for controllers, components, directives, services and filters, mocking and stubbing, best practices, and resources for further reading on AngularJS testing.
React Hooks were introduced to help address issues with React class components like difficulty reusing stateful logic. Hooks allow using state and other React features without writing classes by calling functions like useState and useEffect. React tracks state updates by relying on the order Hooks are called rather than class instances. Custom Hooks allow extracting component logic into reusable functions.
This document discusses testing in iOS applications. It begins by introducing the author and their background. It then discusses reasons for testing like reliability, regression testing, and confidence during refactoring. Potential issues with testing like heavy UI dependence and non-testable code are addressed. The document recommends separating UI and service code for better testability. It demonstrates the Kiwi and OCMock testing frameworks and provides examples of testing classes, dependencies, and private/static methods in an isolated way without heavy mocking. It emphasizes best practices like writing tests first and using version control properly.
Unit testing of java script and angularjs application using Karma Jasmine Fra...Samyak Bhalerao
The document discusses unit testing of JavaScript and AngularJS applications using the Karma-Jasmine framework. It covers what testing and unit testing are, introduces the Karma test runner and Jasmine testing framework, and provides details on setting up Karma configuration files and writing tests using Jasmine specifications and matchers. The document also outlines how to test various aspects of AngularJS applications like controllers, services, directives and HTTP requests.
Smalltalk provides many reflective features, yet behavioral reflection is limited. Pharo provides reflective features that go beyond standard Smalltalk.
The lecture will present Reflectivity, a framework for fine-grained behavioral reflection. It allows to annotate the AST with MetaLinks, alowing meta-objects to change behavior down to a single operation.
After a overview of the framework, we show how MetaLinks are used in Pharo to realize IDE tools such as BreakPoints and Code Coverage.
The document discusses React patterns and hooks. It covers topics like inheritance, composition, mixins, render props, higher order components (HOCs), and React hooks. Some key points:
- Inheritance and composition are approaches to code reuse in object-oriented programming. React uses composition over inheritance.
- Mixins were introduced in 2015 for code reuse but are now deprecated due to issues. Render props and HOCs are preferred patterns.
- Render props and HOCs allow code and state to be shared across components. Render props have fewer levels of nesting while HOCs are better for applying multiple concerns.
- Hooks were introduced to overcome class component limitations and support functional components with local state and lif
Struts 2 interceptors are components that execute before and after the rest of a request and can alter the workflow, handling tasks like validation, exception handling, and data transfer. Interceptors run in a defined order specified in XML or annotations and are used to associate interceptor functionality with actions. Common interceptors provide functionality for data transfer, logging, validation, exception handling, and preventing duplicate form submissions.
The document discusses JavaScript functions, classes, and regular expressions. It covers:
1) How functions are defined and invoked in JavaScript and the different ways functions can be invoked like as methods, constructors, or indirectly.
2) How classes are implemented in JavaScript using prototypes and constructor functions to define behaviors shared across objects.
3) How regular expressions can be used to describe patterns in strings using special characters like character classes, repetition, and other techniques.
This document provides an overview of JavaScript core concepts including objects, functions, scope, prototypes and more. It discusses how objects are created using literals, the new operator and Object.create. It also covers reflection using typeof and hasOwnProperty. Functions are described including invocation patterns, arguments, return, closures and arrow functions. Scope, prototypes and the prototype chain are explained.
React js use contexts and useContext hookPiyush Jamwal
The document discusses the useContext hook in React. It explains that hooks are special functions that start with "use" and are analogous to class component methods. The useContext hook allows components to access data from their parent context without having to pass props down through each level. Without useContext, data would need to be passed through props from the parent component to child components. With useContext, a Context Provider wraps components and provides a value that can be accessed using useContext in any child component without passing props.
This document discusses function parameters and how values are passed into functions in Python. It explains that parameters hold the values passed as arguments during a function call. Parameters act as variables inside the function that can be used, but changes to the parameter do not affect the original argument as Python passes arguments by value rather than by reference. The document provides examples of functions with single and multiple parameters as well as how to return multiple values from a function.
A step towards the way you write the code in React application.In this presentation, I have given introduction about React hooks. Why we need it in our react applications and describe about the two most commonly used React Hooks API useState and useEffect. I also given the links of code snippets I added in these slides
AngularJS Unit Testing w/Karma and Jasminefoxp2code
This document provides instructions for setting up Angular unit testing with Karma and Jasmine. It discusses initializing Karma and Jasmine via NPM, configuring Karma, adding Angular and Angular mocks via Bower, writing describe and it blocks for tests, and using matchers and mocks like $httpBackend. The live coding section at the end indicates the document will demonstrate these concepts in real tests.
The document discusses how to create a custom transformer in Mule by implementing the AbstractTransformer interface and overriding its methods. It provides an example of a KeyTransformer class that takes the source object, gets its string value, and prepends "Hello " to a substring. The document explains that this custom transformer can then be added via the Custom Transformer component in Mule to apply this transformation.
This lightning talk discusses replacing threads with actors for making concurrent service calls in web applications. It describes how actors provide an alternative concurrency model that can be more resource efficient than threads. The talk shows how to implement a master/worker pattern using Akka actors to dispatch work to remote services in parallel from a servlet, collecting the responses to render the page. Key advantages of the actor model include easier reasoning about concurrency and built-in supervision to restart failed actors.
Functions in programming have a definition including a return value, name, parameter list, and body of statements. To declare a function, the def keyword is used followed by the function name and parameters in parentheses. Functions are called by writing the function name followed by parentheses containing any parameters and can return a value.
Test-Driven Development of AngularJS ApplicationsFITC
The document discusses test driven development for AngularJS applications. It outlines problems with traditional front-end development approaches like jQuery manipulation and lack of structure/modularity. The solution presented uses Node.js, NPM, Bower, Grunt, Jasmine and other tools to automate tasks, add structure and enable testing. Features of an example task tracking app are developed using a test-first approach with end-to-end and unit tests. The app is built incrementally by splitting development into small features and writing tests for each.
The document discusses the Command design pattern, which encapsulates requests as objects so that different requests can be parameterized, queued, logged, or made undoable. The pattern addresses the need to issue requests without knowing the operation or receiver. A command defines an interface for executing an operation, concrete commands bind a receiver to an action, and a client creates concrete commands while an invoker carries out the request.
The return statement ends function execution and returns a value to the calling statement. It can return values from built-in functions or user-defined functions. Variables defined inside a function are local and hidden from other functions, while global variables defined outside functions can be accessed throughout the program. Local variables only exist during function execution and are destroyed afterward.
This document discusses AngularJS unit testing. It covers why unit testing is important, setting up a basic testing environment with tools like Karma and Jasmine, writing different types of tests for controllers, components, directives, services and filters, mocking and stubbing, best practices, and resources for further reading on AngularJS testing.
React Hooks were introduced to help address issues with React class components like difficulty reusing stateful logic. Hooks allow using state and other React features without writing classes by calling functions like useState and useEffect. React tracks state updates by relying on the order Hooks are called rather than class instances. Custom Hooks allow extracting component logic into reusable functions.
This document discusses testing in iOS applications. It begins by introducing the author and their background. It then discusses reasons for testing like reliability, regression testing, and confidence during refactoring. Potential issues with testing like heavy UI dependence and non-testable code are addressed. The document recommends separating UI and service code for better testability. It demonstrates the Kiwi and OCMock testing frameworks and provides examples of testing classes, dependencies, and private/static methods in an isolated way without heavy mocking. It emphasizes best practices like writing tests first and using version control properly.
Unit testing of java script and angularjs application using Karma Jasmine Fra...Samyak Bhalerao
The document discusses unit testing of JavaScript and AngularJS applications using the Karma-Jasmine framework. It covers what testing and unit testing are, introduces the Karma test runner and Jasmine testing framework, and provides details on setting up Karma configuration files and writing tests using Jasmine specifications and matchers. The document also outlines how to test various aspects of AngularJS applications like controllers, services, directives and HTTP requests.
Smalltalk provides many reflective features, yet behavioral reflection is limited. Pharo provides reflective features that go beyond standard Smalltalk.
The lecture will present Reflectivity, a framework for fine-grained behavioral reflection. It allows to annotate the AST with MetaLinks, alowing meta-objects to change behavior down to a single operation.
After a overview of the framework, we show how MetaLinks are used in Pharo to realize IDE tools such as BreakPoints and Code Coverage.
The document discusses React patterns and hooks. It covers topics like inheritance, composition, mixins, render props, higher order components (HOCs), and React hooks. Some key points:
- Inheritance and composition are approaches to code reuse in object-oriented programming. React uses composition over inheritance.
- Mixins were introduced in 2015 for code reuse but are now deprecated due to issues. Render props and HOCs are preferred patterns.
- Render props and HOCs allow code and state to be shared across components. Render props have fewer levels of nesting while HOCs are better for applying multiple concerns.
- Hooks were introduced to overcome class component limitations and support functional components with local state and lif
Struts 2 interceptors are components that execute before and after the rest of a request and can alter the workflow, handling tasks like validation, exception handling, and data transfer. Interceptors run in a defined order specified in XML or annotations and are used to associate interceptor functionality with actions. Common interceptors provide functionality for data transfer, logging, validation, exception handling, and preventing duplicate form submissions.
The document discusses JavaScript functions, classes, and regular expressions. It covers:
1) How functions are defined and invoked in JavaScript and the different ways functions can be invoked like as methods, constructors, or indirectly.
2) How classes are implemented in JavaScript using prototypes and constructor functions to define behaviors shared across objects.
3) How regular expressions can be used to describe patterns in strings using special characters like character classes, repetition, and other techniques.
This document provides an overview of JavaScript core concepts including objects, functions, scope, prototypes and more. It discusses how objects are created using literals, the new operator and Object.create. It also covers reflection using typeof and hasOwnProperty. Functions are described including invocation patterns, arguments, return, closures and arrow functions. Scope, prototypes and the prototype chain are explained.
This document discusses predefined and user-defined functions in JavaScript. It explains that functions allow code to be reused by passing control between the call and definition. Both built-in functions like alert() and user-defined functions can be created. User-defined functions are defined with the function keyword and name, may accept parameters, and control returns to the call site after execution. Functions encapsulate reusable blocks of code.
This document discusses patterns in JavaScript including object creation patterns using literals, the new operator, and Object.create(). It also covers function invocation patterns like function, method, constructor, and indirect invocation. Additionally, it summarizes the revealing prototype and revealing module patterns for organizing JavaScript code.
This document discusses various patterns in JavaScript for creating and working with objects. It begins with an overview of creating objects using literals, the new operator, and Object.create(). It then covers functions, including anonymous functions, nested functions, and passing variables in functions. Invocation patterns like function, method, constructor, and indirect invocation are explained. The revealing prototype and revealing module patterns are introduced as ways to structure JavaScript code. The presenter's contact information is provided at the end.
- Objects in JavaScript store key-value pairs and can contain nested objects and functions. Functions stored as object properties are called methods.
- The this keyword refers to the object a method is called on. Functions can be declared, assigned to variables as expressions, or used as constructor functions with new.
- Scopes in JavaScript are determined lexically at compile time. Variables are stored in execution contexts and functions form closures by maintaining references to outer scopes even after execution leaves them.
- JavaScript uses prototypal inheritance where objects inherit directly from other objects via the internal [[Prototype]] property. The prototype is used to lookup properties not found on the object itself.
JavaScript and popular programming paradigms (OOP, AOP, FP, DSL). Overview of the language to see what tools we can leverage to reduce complexity of our projects.
This part goes over language features and looks at OOP and AOP with JavaScript.
The presentation was delivered at ClubAJAX on 2/2/2010.
Blog post: http://lazutkin.com/blog/2010/feb/5/exciting-js-1/
Continued in Part II: http://www.slideshare.net/elazutkin/exciting-javascript-part-ii
JavaScript basics
JavaScript event loop
Ajax and promises
DOM interaction
JavaScript object orientation
Web Workers
Useful Microframeworks
This presentation has been developed in the context of the Mobile Applications Development course, DISIM, University of L'Aquila (Italy), Spring 2014.
http://www.ivanomalavolta.com
The document discusses JavaScript concepts including functions, scope, closures, context, constructors, methods, and object-oriented programming. Some key points:
- Functions are treated as values that can be assigned to variables or passed as arguments.
- Only functions have scope; blocks like if/else do not create scope. Variables declared without var are global.
- Inner functions maintain access to outer functions' variables even after execution (closures).
- Context refers to the object a function is called on, maintained through the this keyword.
- Constructors use the new operator to create object instances. Methods can be public, private, or privileged.
This document contains the slides from a presentation on advanced JavaScript and object-oriented programming concepts. The presentation covers topics like functions, scopes, closures, objects, classes/prototypes, and more. It provides code examples and explanations for each concept. The slides are from a software engineer presenting to help others learn JavaScript programming.
The document discusses different ways to declare variables in JavaScript. There are three main keywords: var, let, and const. Var declares variables with function scope, let declares block-scoped variables, and const declares block-scoped variables that cannot be reassigned.
The document provides an overview of functions in C++. It discusses the basic concepts of functions including declaring, defining, and calling functions. It covers function components like parameters and arguments. It explains passing parameters by value and reference. It also discusses different types of functions like built-in functions, user-defined functions, and functions with default arguments. Additionally, it covers concepts like scope of variables, return statement, recursion, and automatic vs static variables. The document is intended to teach the fundamentals of functions as building blocks of C++ programs.
The document provides an overview of functions in C++. It discusses the basic concepts of functions including declaring, defining, and calling functions. It covers different types of functions such as built-in functions, user-defined functions, and functions that return values. The key components of a function like the prototype, definition, parameters, arguments, and return statement are explained. It also describes different ways of passing parameters to functions, including call by value and call by reference. Functions allow breaking down programs into smaller, reusable components, making the code more readable, maintainable and reducing errors.
An introduction to the complex single page web application framework known as AngularJs. An attempt to overview the high-level aspects of the framework, and to supply references for further exploration.
ave time learning on your own. Start Building with React, MongoDB, Express, & Node. The MERN Stack.
Learning a new JavaScript framework is difficult. You can spend weeks learning new concepts. If an online example doesn’t work, you may spend countless hours Googling, searching Stack Overflow and blogs for the solution.
Take the fast track and learn from an experienced Senior Software Engineer and professional instructor!
About this Course
This highly interactive course features a large amount of student labs and hands-on coding. You will be taught how to assemble the complete stack required to build a modern web app using React.js, MongoDB (a NoSQL database) and Express (a framework for web application servers). This course will also cover many other tools that go into building a complete web application: React Router, React-Bootstrap, Redux, Babel, and Webpack.
What You Will Learn
• How to use modern JavaScript features
• Webpack
• Node & Express
• Reading and writing data to a MongoDB database
• Babel
• React
• State Management with Redux
• Mongoose
• And More!
A brief introduction to javascript test driven development (TDD) towards several point of views by using qUnit, Karma & Jasmine, NodeJS tape module and custom frameworks.
EasyMock is a framework for creating mock objects in Java using proxies. It allows mocking object dependencies to enable isolated unit testing. There are two main ways to create mock objects in EasyMock - directly or through a mock control. Behavior of mock objects can be recorded by adding expectations of method calls and their returns, including exceptions. The mock's lifecycle involves creating it, expecting behaviors, replaying previously recorded expectations, and verifying calls.