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

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


2 Answers

Steven Parker
Steven Parker
216,865 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.