Functional Programming in JavaScript

Chapter 7. Functional optimizations

This chapter covers

• Indicating where functional code is performant
• Examining the internals of JavaScript function execution
• Implications of nesting function contexts and recursion
• Optimizing function evaluation with lazy evaluation
• Speeding up program execution with memoization
• Unwinding recursive calls with tail recursive functions

We should forget about small efficiencies, say about 97% of the time ... premature optimization is the root of all evil. Yet we should not pass up our opportunities in that critical 3%.

Donald Knuth, The Art of Computer Programming

Always optimize last, or so they say. In previous chapters, you learned how to write and test your functional code; and now, nearing the end of ...