A JavaScript Nightmare

@manucastrillonm

JavaScript is a weird language

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Ok no... Is not that weird

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Coercion

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Coercion

Forces a variable of a certain type to have the behavior of a different one.

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Why do we need this?

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JavaScript is a non-typed language

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Duck Typing

“If it walks like a duck and it quacks like a duck, then it must be a duck”

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Don't worry!

coercion

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Equality operator

==

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Addition operator

+

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Subtraction operator

-

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Truthy and Falsy

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In a boolean context, all values are True except

  • false

  • 0

  • ""

  • ''

  • null

  • undefined

  • NaN

  • document.all

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Conclusion

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Done

JS coercion

By Manu Castrillón

JS coercion

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