Author: admin
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$ and $$ Variables
We know that PHP uses the convention of prefixing the variable names by the “$” symbol. PHP also has the provision of declaring dynamic variables by prefixing two dollar symbols ($$) to the name. A variable variable (or a dynamic variable) can be set and used dynamically. The declaration of a normal variable is like…
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How is Node.js better than other most popular frameworks?
Based on the following criteria, we can say that Node.js is better than other most popular frameworks:
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What do you understand by callback hell in Node.js?
Callback hell is a phenomenon that creates a lot of problems for a JavaScript developer when he tries to execute multiple asynchronous operations one after the other. A function is called an asynchronous function when some external activity must complete before processing a result. It is called asynchronous because there is an unpredictable amount of…
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PHP var_dump() Function
ne of the built-in functions in PHP is the var_dump() function. This function displays structured information such as type and the value of one or more expressions given as arguments to this function. This function returns all the public, private and protected properties of the objects in the output. The dump information about arrays and…
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Why is Node.js Single-threaded?
Node.js is a single-threaded application with event looping for async processing. The biggest advantage of doing async processing on a single thread under typical web loads is that you can achieve more performance and scalability than the typical thread-based implementation.
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Echo/Print
In PHP, both echo and print statements are used to render the output either on the browser or the PHP console. Both of them are not functions but they are language constructs. Hence, parentheses should not be used with either of them. The “echo” Statement in PHP The echo statement is used with following syntax − The echo statement outputs one or more…
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How can you manage the packages in your Node.js project?
We can manage the packages in our Node.js project by using several package installers and their configuration file accordingly. Most of them use npm or yarn. The npm and yarn both provide almost all libraries of JavaScript with extended features of controlling environment-specific configurations. We can use package.json and package-lock.json to maintain versions of libs…
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Explain the working of Node.js?
The workflow of a Node.js web server typically looks like the following diagram. Let us see the flow of operations in detail:
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What is the difference between JavaScript and Node.js?
Difference between JavaScript and Node.js The following table specifies the crucial differences between JavaScript and Node.js: Comparison features JavaScript Node.js Type JavaScript is a programming language. More precisely, you can say that it is a scripting language used for writing scripts on the website. Node.js is an interpreter and run time environment for JavaScript. Utility…
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What do you understand by the first class function in JavaScript?
When functions are treated like any other variable, then those functions are called first-class functions. Apart from JavaScript, many other programming languages, such as Scala, Haskell, etc. follow this pattern. The first class functions can be passed as a param to another function (callback), or a function can return another function (higher-order function). Some examples…