Functional Programming

programming with knowing the difference between pure code (give the same result each time ) and impure code( running two-times different from once"depends on that side effect").

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how to distinguishes and identify functional programming and procedural and object-oriented ??

• Procedural: sequential steps.
• object-oriented: communicating object.
• functional programming>>> based in pure functions >> give the same result with same input "easily reused"

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Higher-order functions: it functions operate other functions (can be token as input and output)(ex. map, filter ). note: it's a tent of functional programming.

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Objects and Inheritance

• prototype-based inheritance: methods or properties related to object allow to use and available in object and descendants.
• class inheritance: still use prototype-based inheritance but much easier and clear.

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** Errors**

• important in debugging.
• Writing Good Error Messages >> ( to be great it need: timestamp, message problem, the message of cause, format, describe level).
• Handling Thrown Errors: way to force use an improper function.

• sooner fail sooner fined bugs.
• away to complete running in javascript is try {} catch (error) {}.

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Error Cheat Sheet " like type error, syntax error,.....) system Error Cheat Sheet "like EACCESS, EADDRINUSE ,ECONNREFUSED,......)

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video: context " the content of this "