As I delved into the intricacies of Javascript's asynchronous behavior within its single-threaded environment, I stumbled upon a comment that caught my attention regarding the following code snippet:
request(..., function (error, response, body)
console.log('foo);
});
callAComputationallyIntensiveSynchronousFunctionThatTakesSixHoursToExecute();
console.log('bar');
'bar' will still come before 'foo' because Javascript always finishes the currently executing function first. An event will never interrupt a function.
I grasp the concept that synchronous functions take precedence over events, but what baffles me is why 'bar' would be displayed before 'foo'. My understanding leads me to believe that an async call should trigger, allowing for other lines of code to run until the response is prepared, subsequently executing the callback function and resuming the code execution accordingly.
In the example provided, it seems that despite the response being ready well in advance of the synchronous function completion, Javascript proceeds to execute the subsequent line of code. This begs the question - what is the rationale behind this behavior?