0_introducing_async_javascript
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Introducing Asynchronous Javascript
Node Tree
Nodes
async_programming | |
content | Asynchronous Programming: a technique that enables programs to start a potentially long-running task while still being responsive to other elements. |
children | event_handlers |
sync_programming | |
content | Synchronous Programming |
children | long_running_sync_fun_unresponsive |
long_running_sync_fun_unresponsive | |
content | Long-running synchronous functions will cause programs to be unresponsive |
parents | sync_programming |
event_handlers | |
content | event handlers |
children | event_handler_is_callback, form_async_programming |
parents | callbacks, async_programming |
form_async_programming | |
content | form of asynchronous programming |
parents | event_handlers |
XMLHttpRequest | |
content | XMLHttpRequest API: allows Http request to remote server. can attach event listeners to notify when done. |
callbacks | |
content | callbacks |
children | callback_hell, cb_code_difficult_to_understand, event_handler_is_callback, event_handlers, func_passed_into_func (description), modern_apis_use_promises |
event_handler_is_callback | |
content | An event handler is a kind of callback |
parents | event_handlers, callbacks |
func_passed_into_func | |
content | Function passed into another function, with the expectation that it will get called at the appropritae time |
parents | callbacks |
cb_code_difficult_to_understand | |
content | callback-based code can get hard to understand when the callback itself has to call functions that accept a callback |
children | common_if_op_breaks_into_async_funcs |
parents | callbacks |
callback_hell | |
content | Callback Hell / pyramid of doom: deeply nested callbacks |
children | modern_apis_use_promises (promises avoid callback hell) |
parents | callbacks |
common_if_op_breaks_into_async_funcs | |
content | Common if you need to perform operation that breaks into series of asynchronous functions |
parents | cb_code_difficult_to_understand |
modern_apis_use_promises | |
content | Modern asynchronous APIs used promises instead of callbacks |
parents | callback_hell, callbacks |