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class declaration constructor Instance methods Static methods extends super Bound instance methods Prototype access :: Class properties Mixins with object assignment
Operators
is and isnt and or not in operator of operator Chained comparisons Floor division // Modulo %% Exponentiation ** Assignment operators Nullish assignment ?=
JavaScript Interop
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CoffeeScript Complete Course / Classes

extends

Learn extends in CoffeeScript with a construct-specific explanation, a unique example, a practical boundary, and a mastery check.

12 min read • Intermediate

extends is an atomic CoffeeScript topic inside Classes. The example below uses the actual construct named by the lesson rather than a generic placeholder.

Focus on what extends changes: the input, binding, control path, object state, collection, runtime effect, or language contract. Then alter one value and verify that the behavior changes for a reason specific to this feature.

Topic-specific example

coffeescript-05-05-extends.coffee
coffeescript Try It Live 
class Animal
  sound: -> "?"
class Dog extends Animal
console.log new Dog().sound()
Edge case / engineering note

Change the key input in this CoffeeScript example and predict the result first; the named construct should be the reason the behavior changes.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

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