Published
Edited
Jan 29, 2020
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3 // I'm a comment. #ComputerCantTouchThis
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3 + 3 //addition
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4 - 3 //subtraction
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2 * 3.2 //multiplication
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1 / 5 //division
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10 % 3 //modulo
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10 ** 3 //exponentiation
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typeof 123
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typeof 0.1
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typeof "this is a string" // denoted by either "string value goes in here",
//'string value in here', or `string value in here`
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typeof 'this is also a string'
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typeof ""
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typeof true // either true of false
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typeof false
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typeof undefined // the only possible value of an undefined type is undefined
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// `typeof` doesn't work with `null` values for backwards compatability reasons.
typeof null
// when checking if something's explicitly `null`, make sure to use null === null
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'bob' + 'mary'
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'Luke, ' + 'I ' + 'am ' + 'your ' + 'father.'
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true && true // the AND (&&) operator checks if both values are true
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//if either one or both ANDed values are false,
true && false
//the operation returns false
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true || true // the OR (||) operator checks if either value is true
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//if one value is false, the result is still true
true || false
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!true //The NOT (!) operator switches the boolean value
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//Order of operations still applies in boolean algebra
!true && false || false || false
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!(true && false) || false || false
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{
var name = 'bob'
return name //this line is to make Observable happy
}
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{
var num = 1
num = 2
return num
}
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{
var one = 1
var two = 2
var three = one + two
return three
}
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{
var firstName = 'Bob'
var lastName = 'Marley'
var fullName = firstName + ' ' + lastName
return fullName
}
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{
var allMenAreMortal = true
var iAmAMan = true
return allMenAreMortal && iAmAMan
}
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function converter (fahrenheit)
{
var Celsius = 0
Celsius = (fahrenheit-32)/(9/5)
return Celsius
}
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function varWars1() {
var smartiesBot = true;
var sourBot = false;
var otherSourBot = sourBot;
return (smartiesBot || sourBot) || otherSourBot
}
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function varWars2() {
var smartiesBot = true;
var sourBot = true;
var otherSourBot = false;
return (smartiesBot || sourBot || otherSourBot)
}
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function varWarsArmageddon() {
var smartyKing = true;
var sourKidKing = false;
var smartiesBot = sourKidKing;// false
var thatOneSourBot = smartyKing;// true
return (smartiesBot || smartyKing) || (!sourKidKing && !sourKidKing) && thatOneSourBot && thatOneSourBot || (!smartiesBot && smartiesBot || !sourKidKing)
}
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