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Austin Whittier
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Published
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Austin Whittier
Edited
Oct 5, 2020
Insert cell
Insert cell
typeof
undefined
Insert cell
{
let
value
;
return
typeof
value
;
}
Insert cell
{
let
value
;
return
value
===
undefined
;
}
Insert cell
{
// uh-oh!
const
undefined
=
'not undefined'
;
let
value
;
return
value
===
undefined
;
}
Insert cell
{
const
undefined
=
'not undefined'
;
let
value
;
return
typeof
value
===
'undefined'
;
}
Insert cell
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
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