| /** Method chaining (like jQuery uses) is an awesome programming technique -- | |
| * | |
| * Here's an example of a Cat class that is built so that the methods can | |
| * be chained together. See example at bottom for using this. | |
| * | |
| */ | |
| class Cat { | |
| constructor(name) { | |
| this._name = name; |
| /** A "decorator" -- a function that: | |
| * - takes a function as its arg | |
| * - returns a "wrapped version" of that function | |
| * | |
| * In this case: the wrapped version runs the real function, | |
| * but keeps track of how long it took to run. | |
| */ | |
| function timeit(fn) { | |
| function wrapper(...args) { |
| from time import time | |
| from random import random | |
| # A "decorator" -- a function that: | |
| # - takes a function as its arg | |
| # - returns a "wrapped version" of that function | |
| # | |
| # In this case: the wrapped version runs the real function, | |
| # but keeps track of how long it took to run. |
| // makes a "lazy array" of all even numbers 2...infinity | |
| function * evens(n = 0) { // "Generator function" | |
| while (true) { | |
| n += 2 | |
| yield n; | |
| } | |
| } | |
| let allEvens = evens() // allEvens is a "generator" |
| import React, { useState, useEffect } from 'react'; | |
| import './App.css'; | |
| /** Hook for validating email-like state. | |
| * - `initVal`: initial state (defaults to null; is not validated!) | |
| * Returns [data, setData] functions, like useState() does. | |
| * | |
| * setData validates email: if input is invalid email string, | |
| * doesn't set & returns false. If valid, sets & returns true. */ |
| <html> | |
| <head> | |
| <style> | |
| #outer { position: relative; left: 0; top: 0; } | |
| #scrollable { width: 10em; height: 5em; overflow: scroll; } | |
| #tooltip { display: none; position: absolute; left: 150px; top: 50px; border: solid 1px black; background-color: goldenrod; padding: 0.5em } | |
| </style> | |
| </head> | |
| <body> |
| def is_palindrome(word, i=0): | |
| """Is word a palindrome? | |
| >>> is_palindrome("noon") | |
| True | |
| >>> is_palindrome("tacocat") | |
| True | |
| >>> is_palindrome("zacbz") |
A. all functions all called with a context — "what was I called on?"
to find the context, look to the "left of the dot" when the function is invoked
eg: foo.bar() means bar will get context of foo
(this only works at all if "bar" is a property of foo --- otherwise, foo.bar itself is just undefined!)
| from app import app | |
| from unittest import TestCase | |
| class MadlibsTestCase(TestCase): | |
| def setUp(self): | |
| self.client = app.test_client() | |
| def test_questions(self): | |
| resp = self.client.get("/") | |
| body = resp.get_data(as_text=True) |
| class N: | |
| """Simple Binary Node class.""" | |
| def __init__(self, val, left=None, right=None): | |
| self.val = val | |
| self.left = left | |
| self.right = right | |
| def __repr__(self): | |
| """Representation; useful for debugging tree.""" |