Variables by assignment String interpolation Arrays Objects Existential operator ? Soaked access ?. Ranges Destructuring assignment Splats Comments

Function arrow -> Bound arrow => Implicit return Default parameters Rest parameters Named functions Higher-order functions IIFE with do Function composition Callbacks

if expression unless postfix if switch while until loop break continue try catch finally

for in arrays for of objects Comprehensions Filtered comprehensions Index in comprehension Object key and value Range iteration by step own property iteration Array mapping comprehension

class declaration constructor Instance methods Static methods extends super Bound instance methods Prototype access :: Class properties Mixins with object assignment

is and isnt and or not in operator of operator Chained comparisons Floor division // Modulo %% Exponentiation ** Assignment operators Nullish assignment ?=

Embedded JavaScript require modules ES module import ES module export Promise usage async functions await JSON parsing DOM querySelector Event listeners

Memoization Guard clauses Object defaults Optional callbacks Configuration merge Grouping values Flattening arrays Unique values Sorting objects Error wrapping