Conventions used

There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, and user input. Here is an example: ”Any attempt to run code that has such issues will immediately cause the interpreter to fail, raising a SyntaxError exception.”

A block of code is set as follows:

 
{const set = function(...items) {  
    this.arr  = [...items];  
    this.add = {function}(item) {  
        if( this._arr.includes(item) ) {  
            return false; (SC-Source)}

Any command-line input or output is written as follows:

 
$ python3 script.py

Some code examples will represent the input of shells. You can recognize them by specific prompt characters:

• >>> for interactive Python shell
• $ for Bash shell (macOS and Linux)
• > for CMD or PowerShell (Windows)

Warnings or important notes appear like this.

Important note

Warnings or important notes appear like this.

Tips and tricks appear like this.

Tips or tricks

Appear like this.