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Callbacks and Higher-Order Functions in JavaScript - Coggle Diagram
Callbacks and Higher-Order Functions in JavaScript
Callbacks
Functions passed as arguments to other functions
Can be used for asynchronous or synchronous code
Allows functions to be more flexible and reusable
Parameters can be passed to the callback function
Executed inside the parent function
Higher-Order Functions
Functions that accept another function as an argument
Can also return a function
Used to abstract, iterate, or modify behavior
Built-in Higher-Order Functions
forEach
: iterates over an array, no return value
map
: iterates and modifies array elements, returns new array
filter
: iterates and filters elements based on a condition, returns new array
reduce
: reduces array elements to a single value, returns a value
Key Concepts
Callback functions are executed at the right time
Arguments can be passed to callbacks
Higher-order functions improve readability and maintainability
Can work with both arrays and objects
Can be implemented manually without built-in methods
Custom Implementation
loop
: manual iteration for arrays or objects
map
,
filter
,
reduce
: custom functions using
loop
Can extend higher-order functions to objects
Provides flexibility for custom iteration logic
Use Cases
Transforming arrays (map)
Filtering arrays (filter)
Aggregating values (reduce)
Iterating and performing side effects (forEach)
Counting, ordering, or computing derived data
Implementing custom control flow with callbacks
Advantages
Code reusability
Clean and readable syntax
Avoids repetitive loops
Makes complex logic composable
Works naturally with asynchronous operations