typeof(true)
!true
typeof(null)
Boolean(null)
!null
typeof(undefined)
Boolean(undefined)
!undefined
10
typeof(10)
Number('22')
Number('Salut')
typeof(NaN)
Number.isNaN('Salut')
Number.isNaN(Number('Salut'))
Number.isNaN(1)
Number.isNaN('1')
1.234567.toFixed(2)
0.1 + 0.2
Number((0.1 + 0.2).toFixed(2))
Math.floor(1.234)
Math.ceil(1.234)
Math.round(1.234)
'Salut'
typeof('Salut')
'Salut' + '!'
saluer = nom => `Salut ${nom} !`
saluer('Machin')
'Salut'.toUpperCase()
'Salut'.toLowerCase()
'Salut'.includes('lut')
'Ceci est une phrase'.split(' ')
typeof(obj)
obj.nom
Object.keys(obj)
obj2 = ({ ...obj, autre: 'x' })
{
const { age } = obj
return age
}
{
const { age, aFaim } = obj
return { age, aFaim }
}
arr1 = [1, 2, 3]
arr2 = [1, 'Salut', true, { x: 2 }]
arr3 = [...arr2, null]
arr4 = [...arr1, ...arr2]
arr5 = [arr1, arr2]
{
const [premier, deuxieme, ...reste] = [1, 2, 3, 4, 5]
return { premier, deuxieme, reste }
}
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