Asynchronous Programming - Reading Assignment

Javascript Programming
#842

  1. What is the difference between synchronous and asynchronous functions?
    With synchronous functions the tasks for Javes need to be carried out one at a time and with asynchronous functions, we are able to have other tasks completed while we wait for a response.

  2. What is callback hell?
    It is a term that is used to describe the act of more complex operations having several functions that need to be carried out; creating many levels and sublevels.

  3. Which technique can help us solve callback hell?
    In the browser this can be aided with the use of promises and with node.js by extending the runtime.

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#843

1. What is the difference between synchronous and asynchronous functions?
Synchronous functions would for example block the client until the operation is complete.
Asynchronous functions allow the operation to be completed in the background while the client is allowed access.

2. What is callback hell?
When callback functions are nested inside each other and depend on the data from the previous function, the code becomes a mess and is difficult to navigate, audit or iterate.

3. Which technique can help us solve callback hell?
Promises. This feature was introduced to deal with asynchronous calls. It will return a resolved or reject some time in the future

Instead of nesting the callbacks, the functions can be chained with the “then” keyword whereby if the promises resolve the asynchronous call, the next function will run.

If any promises reject, the catch keyword can be used at the end to deal with them.

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#844

1.A Synchronous function gets executed line after line. Asynchronous functions can be initiated and then put aside until a later date. For exampe if we want to use an API we have to work with Asynchronous functions since we don’t now exactly when we get the response.
2. Callback hell is any code where the use of function callbacks in asynchrounous code becomes obscure or difficult to follow. Generally, when there is more than one level of indirection, code using callbacks can become harder to follow.
3.We can use comments, promises to help us solve the callback hell.
In Node.js, we can use a different approach. By extending the runtime, we can abstract away the asynchronicity and write code that looks sychronous

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#845
  1. What is the difference between synchronous and asynchronous functions?

Synchronous functions require continuous commitment of resources until execution has been completed, where asynchronous functions can be initiated, put aside, then recommissioned at a later time when needed.

  1. What is callback hell?

It is an inordinate number of levels and sub-levels of nested functions within a program.

  1. Which technique can help us solve callback hell?

Promises, from the simple built-in JQuery Promise library.

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#846
  1. What is the difference between synchronous and asynchronous functions? Synchronous functions can only run one at a time while asynchronous functions can run in parallel.
  2. What is callback hell? It´s when we have many nested functions making the code almost unreadable and very difficult to understand.
  3. Which technique can help us solve callback hell? Promises.
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#847

1.) A Synchronous program code runs straight along, when the function relies on another code that dont has been arrived, it has to wait… Asynchronous codes allows us to make other actions, while waiting for results.
2.) When you got callbacks and more callbacks inside it and so on…
3.) Promises can solve callback hell situations.

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#848
  1. What is the difference between synchronous and asynchronous functions?
    In JavaScript, because it is single-threaded, the synchronous function occupies the thread until its completion, while asynchronous tasks can be initiated and then put aside until a later time, while the following task in the event loop gets started. All the process is managed by an additional background thread.
  2. What is callback hell?
    Callback hell refers to the levels and sub-levels produced by nested functions.
  3. Which technique can help us solve callback hell?
    In the browser promises are used to chain callbacks and deal with errors.
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#849
  1. Asynchronous tasks can be initiated and then put aside until a later date while the next task is called on the “to do list” of commands, while synchronous tasks will continuously run without doing any other tasks until its completion.
  2. Where there is excessive callbacks within multiple levels of nested functions.
  3. It uses a simple built-in promise library to assist in chaining callbacks and dealing with call errors.
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#850
  1. Synchronous functions are functions that have to wait to be executed one after another, asynchronous functions allow for multiple tasks to completed at the same time.
  2. Callback hell is referring to the fact that nested functions in callbacks can end up being giant and messy, creating a really long functions for even relatively short, quick things.
  3. Promises.
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#851
  1. Synchronous Functions is a single-threaded function, only one code can be run at a time while Asynchronous Functions multiple codes can be executed at the same time simply by extending run-time.
  2. Callback hell exist in a situation where multiple functions are nested together in one function. where for completion, functions are inter-dependent.
  3. PROMISE is a technique use to handle callback hell.
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#852

What is the difference between synchronous and asynchronous functions?

While synchronous functions demands full atention (from the code) untill its finished, the asynchronous function can be put aside while it waits for a condition to be finished so it can be completely done.

What is callback hell?
A enormous amout of nested functions within a equally enormous amount of levels and sub-levels of operations.

Which technique can help us solve callback hell?
One way is by using promises, other way is extending the runtime within node.JS. Among the ways to do it, one is by using the sub-library Fibers.

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#853

  1. Synchronous functions take the browser’s full attention to execute and no other code can be executed until the task is complete. With asynchronous functions the browser can perform other tasks while waiting for the function to finish.

  2. When using several nested callback functions your code can become a mess that is too confusing and hard to read.

  3. With promises, or by extending the runtime with node.js to make code that appears more asynchronous.

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#854
  1. Synchronous functions block further execution of the program. Asynchronous functions do not block further execution of the program.
  2. A function within a function within a function, forming a nested loop is called callback hell.
  3. The use of Promises can solve callback hell.
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#855

  1. What is the difference between synchronous and asynchronous functions?
    Sequential, line by line execution of function till completion-synchronous
    Parts of the code deferred to be later revisited, for example where functions get incompletely excecuted, is defined as asynchronous.

  2. What is callback hell?
    Due to multiple call backs, one within another, the code may become unmanageable or difficult to follow

  3. Which technique can help us solve callback hell?
    Promises

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#856
  1. Synchronous functions occupies JS thread until they are finished. However asynchronous functions can be interrupted by other functions while waiting for some responses.
  2. Callback hell is a situation when there is a lot of nested callback for specified functionality. It is not intended due to difficulty to manage and debug such code.
  3. Callback hell can be resolved by so called promises.
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#857

What is the difference between synchronous and asynchronous functions?
A synchronous function requires the full attention of the browser until the function is executed. An asynchronous function can be initiated but can be put aside until it waits for the result of a callback.

What is callback hell?
Callback hell is caused by coding with complex nested callbacks. Each callback takes an argument that is the result of one of the previous callbacks. So if there is an error in one function, all of the other functions are affected.

Which technique can help us solve callback hell?
By using promises, we can defer the execution of a code block until an async request is completed. This way, other operations can keep running without interruption.

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#858
  1. What is the difference between synchronous and asynchronous functions?
    Synchronous functions block the thread until completion whereas asynchronous functions are initiated and put aside while other functions may be called.
  2. What is callback hell?
    Having to deal with nested callback functions.
  3. Which technique can help us solve callback hell?
    By extending the runtime, we can abstract away the
    asynchronicity and write code that looks sychronous
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#859

1.- Synchronous functions have to start and finish but asynchronous functions can execute and then continue with another task while the previous functions is waiting on a reply.
2.- Callback hell is an undesirable situation whereby several nested callback functions are needed in order to perform relatively simple tasks
3.- While using jquery we can use “promises” - This allows us to chain callbacks and deal with errors (this is prebuilt in the library).

@charlie_crypto Hello, I used your answer for number 2 it was way more clear than what i wrote, thanks!

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#860
  1. Synchronous functions have to be executed one at a time, while asynchronous functions can be iniciated and put aside until later.
  2. Is a slang used to describe and unwieldy number of nested “if” statements or functions.
  3. In the browser, a common pattern to deal with excessive callbacks is to use promises. jQuery ships with a simple built-in promise library that enables us to chain callbacks and deal with errors.
    But in Node.js, we can use a different approach, extending the runtime.
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#861
  1. While synchronous functions can run only one section of the code at the time, asynchronous function can run several sections
  2. This is when many functions which receive other functions, and so on on many levels, which causes mess and hard to read code.
  3. Promises is solution to manage callback hell.
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