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JavaScript Asynchronous Programming with JavaScript Asynchronous JavaScript with Callbacks Managing Nested Callbacks

Hernan Diaz
Hernan Diaz
7,197 Points
Posted by Hernan Diaz
Hernan Diaz
7,197 Points

Syncronous or asyncronous

when does some file is executed asyncronously?

I can't yet understand when a file is going to follow the sequence or when it won't

thanks

2 Answers

Steven Parker
Steven Parker
231,275 Points
Steven Parker
Steven Parker
231,275 Points

Code execution is synchronous unless it is triggered by some event. Functions that perform asynchronously will nearly always take a callback argument that will be executed at some future time. Callbacks can usually be identified because they are referenced but not invoked. For example:

sample = myfunc(otherfunc(), 1200);    // synchornous, "otherfunc" will be called now
timeid = setTimeout(otherfunc, 1000);  // asynchronous, "otherfunc" will be called later

The asynchronous mechanisms should be clearly pointed out when they are introduced in the courses.