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Practice JavaScript concepts
// var message = "hello world";
// console.log(message);
// var x = "hey";
// var y = 10;
// console.log(x);
// console.log(y);
// console.log(x + y);
// y = " is for horses";
// console.log(x + y);
// var x = 1,
// y = 2,
// z = "3";
// console.log(x + y + z);
// Numbers
// var integer_number = 1,
// float_number = 1.23;
// // console.log(integer_number + float_number);
// // // Booleans
// var is_cool = true;
// // console.log(is_cool + " dat")
// // Arrays
// var my_stuff = [
// integer_number,
// float_number,
// is_cool
// ];
// console.log(my_stuff);
// Hashes
// var capitals = {
// LA: "Baton Rouge",
// TX: "Austin",
// GA: "Atlanta"
// };
// console.log(capitals["LA"]);
// Null and undefined
// var x;
// Variables that haven't been initialized are undefined.
// console.log(x); // undefined
// But they aren't null
// console.log(x === null); // false
// Unless you actually make them null
// x = null;
// console.log(x); // null
// console.log(x === null); // true
// console.log(x === undefined); // false
// OR, use 'type coercion'... 2 equal signs in JS will change the value
// rather than simply compare. So BE CAREFUL! CUIDADO! PROSEXE!
// console.log(x == undefined); // true
// This variable is in the Global scope
// var x = "I'm a global variable called x!";
// console.log(x);
// // Define a function called someFunction
// function someFunction(){
// // This variable only exists inside the function (it's local)
// var y = "I'm a local variable called y!";
// console.log(x);
// console.log(y);
// // this is bad. don't do it.
// x = "I'm now a BAD local variable called x"
// console.log(x);
// // this is automatically global - don't do it! always use var for declaring new variables.
// z = 10;
// console.log(z);
// };
// someFunction();
// console.log(x);
// console.log(z);
// Operators
// var x = 10,
// y = 5;
// console.log(x + y);
// console.log(x - y);
// console.log(x * y);
// console.log(x / y);
// console.log(x % y); //modulus, or remainder
// console.log(x > y); // true
// console.log(x < y); //false
// console.log(x >= y); //true
// console.log(x <= y); //false
// console.log(x === y); // false
// console.log(x !== y); //true
// var a = true,
// b = false;
// console.log(a && b); // and... false
// console.log(a || b); // or... true
// Conditionals (if statements)
// var x = 10,
// y = "ten";
// if (x > y){
// console.log("x is greater than y");
// } else if (x < y){
// console.log("x is less than y");
// } else {
// console.log("x is neither less than nor greater than y");
// }
// Loops
// C-style JavaScript loop
// var x = [1, 2, 3, 4, 5];
// for (var i = 0; i < x.length; i++){
// console.log(x[i]);
// }
// For each loop
// x.forEach(function (element){
// console.log(element);
// });
// var i = 0;
// while (i < x.length){
// console.log(x[i]);
// i++ // same as i += 1
// }
// Functions
// a function with explicit arguments
function sumExplicitly(a, b){
return a + b;
}
var sum = sumExplicitly(4, 5); // 9
console.log(sum);
// a function with implicit arguments
// function sumImplicitly(){
// var total = 0;
// for (var i = 0; i < arguments.length; i++){
// total -= arguments[i];
// }
// console.log(total);
// }
// sumImplicitly(1, 2, 3, 4, 6, 125, 231241);
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