Published
Edited
Aug 15, 2022
1 fork
3 stars
+(12.345678).toFixed(2)
(new Date()).toLocaleDateString([],{
weekday: "long",
month: "short",
day: "numeric",
hour: "numeric",
minute: "2-digit",
year: "numeric",
timeZoneName: "long"
})
(new Date()).toLocaleDateString([],{
weekday: "long",
month: "short",
day: "numeric",
})
(new Date("2021-06-23T02:42:27.46+00")).toLocaleTimeString([],{
minute: '2-digit',
second: '2-digit',
fractionalSecondDigits: 1
// options: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Intl/DateTimeFormat/DateTimeFormat
})
(new Date("2021-06-23T02:42:27.46+00")).toLocaleTimeString()
// Works in node.js
// (str => Buffer.from(str, 'base64').toString('utf-8'))("")
new Date(1627777714000)
window.btoa('Hello, world!')
window.atob('SGVsbG8sIHdvcmxkIQ==')
array_of_just_the_values = [{a:1},{a:3},{a:7},{a:13}].map( row => row.a )
sum_of_array = [1,3,7,13].reduce( ( sum, cur ) => sum + cur )
those_two_combined = [{a:1},{a:3},{a:7},{a:13}].map( row => row.a ).reduce( ( sum, cur ) => sum + cur )
more_complex_object_from_simple_array = [0,1,0,2,0,3].map(d=>{
return { is_zero: d===0, value: d }
})
string_converted_to_code_points = 'HFI!'.split('').map(d=>d.charCodeAt(0))
code_points_converted_to_string = [72,70,73,33].map(d=>String.fromCharCode(d)).join('')
sort_array_based_on_object_properties = [{foo:1,bar:8},{foo:2,bar:4}].sort((a, b) => a.bar - b.bar)
array_of_unique_values_from_an_array = {
const my_array = ["foo", "bar", "foo", "bat", "bat", 1, "1", true];
return [...new Set(my_array)]
}
quick_array_filled_with_range = Array.from({length: 20}, (x, i) => i + 4) // 4 is the floor, if desired
shift_gets_me_the = ["first element","last element"].shift()
pop_gets_me_the = ["first element","last element"].pop()
(6652).toString(2).padStart(16, '0')
( 0b0010011 ^ 0b1111111 ).toString(2) // toString(2) only there so we can see the resulting binary
// could also be written 19 ^ 127
( ~0b0010011 >>> 0 ).toString(2) // toString(2) only there so we can see the resulting binary
map_to_range = (value, in_min, in_max, out_min, out_max) =>
(value - in_min) * (out_max - out_min) / (in_max - in_min) + out_min
map_to_range(5, 0, 10, 0, 500)
"1.19" > "1.2"
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