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51 lines
982 B
51 lines
982 B
4 years ago
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## Seeker of Truth
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### Truthy and Falsy
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In JS, all values are either **truthy** or **falsy**, this means if used in a condition, truthy values will validate the condition while falsy values would not.
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Here is the list of falsy values:
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- `undefined` and `null`
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- the numbers `0` and `NaN`
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- the empty string `''`
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- and the boolean `false` of course
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All other values are truthy, note that empty arrays and empty objects are truthy, but the empty string is not.
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```js
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if ('') {
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console.log('Since empty string are falsy, this will never log')
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}
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if ('hello') {
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console.log('this will always log as the string is not empty')
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}
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```
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### Operator `!`
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The `!` (NOT operator) can be used to convert a truthy value to `false` or a falsy value to `true`.
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example:
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```js
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let money = 0
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let noMoney = !money
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console.log(noMoney) // true
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```
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In this case, 0 is falsy, so the `!` return the value `true`
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### Instructions
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R
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```js
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let truth = 0
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if (!truth) {
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console.log()
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}
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```
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