JavaScript Functions

What you'll learn

• Why functions are values, and what that lets you do
• Closures — the mechanism, not just the buzzword
• The four ways 'this' gets bound
• Higher-order functions in everyday code
• Currying and partial application, used right
• Common bugs and how to spot them at a glance

1. 01
   Functions are values

   First-class, plain and simple — and what that buys you.
   12 min
2. 02
   Declarations vs expressions

   Hoisting, named expressions, and what 'this' has to do with it.
   13 min
3. 03
   Parameters and arguments

   Defaults, rest, destructuring — modern function signatures.
   14 min
4. 04
   Closures

   Why a returned function still 'remembers' its surroundings.
   18 min
5. 05
   this, finally

   The four binding rules, in order. No more guessing.
   16 min
6. 06
   Arrow functions

   What they aren't (it's not just shorter syntax).
   12 min
7. 07
   Higher-order functions

   Functions that take or return functions, and why you already use them.
   13 min
8. 08
   Currying and partial application

   Two ideas, often confused, both useful.
   11 min
9. 09
   Common pitfalls

   Loops + closures, lost 'this', accidental globals.
   11 min