Appendix B. Reading C++ for JavaScript Programmers
The examples in this book are all presented in C++. That’s the language I do most of my programming in, and it’s the language I’m most proficient in.
If you’re a JavaScript programmer, don’t despair—the Rules are still useful! You don’t need to learn how to program in C++ in order to read the examples in this book. Code is code, basically—a loop is a loop, variables are variables, and functions are functions. There are some cosmetic differences, but the basic ideas in this book’s C++ examples translate pretty directly to JavaScript, even when that translation isn’t immediately obvious!
This appendix explains how to do that translation—how to read C++ and convert it in your head to the JavaScript equivalent. You won’t be able to write C++ code after working your way through this appendix—that would take a whole book—but you should be much more capable of reading it.
Types
Time for an example! Here’s a simple function that calculates the sum of an array of numbers, first in JavaScript:1
functioncalculateSum(numbers){letsum=0;for(letnumberofnumbers)sum+=valuereturnsum;}
And then in C++:
intcalculateSum(constvector<int>&numbers){intsum=0;for(intnumber:numbers)sum+=number;returnsum;}
Um…it’s the same code. Maybe we don’t need an appendix after all.
Or maybe we do. JavaScript syntax was heavily influenced by C syntax, and I won’t have to explain what curly braces and semicolons mean like I ...