Removing the largest number from an array
To remove the largest value from an array of numbers we first need to find that number and can then filter it out.
Read full articlePicking object properties
JavaScriptAll snippets in this category →
Posted on July 12, 2020With Array.prototype.reduce(), we can extract only the properties of an object we want to pass along.
This is particularly useful when you want to send partial data to or from an API. You can pick what information you want to reveal, while keeping sensitive data hidden.
// we don’t want to pass all of this information along all the time
const user = {
email: "ckent@dailyplanet.com",
password: "i-am-superman",
username: "clarkkent"
}
// this function receives an object and a list of properties to extract
const pick = (object, props) => props.reduce((picked, prop) => ({
...picked,
[prop]: object[prop]
}), {})
// we can use `pick` to get only the information we need
const condensedUser = pick(user, ["username", "email"])
// ⇒ {
// username: "clarkkent",
// email: "ckent@dailyplanet.com"
// }// we don’t want to pass all of this information along all the time
const user = {
email: "ckent@dailyplanet.com",
password: "i-am-superman",
username: "clarkkent"
}
// this function receives an object and a list of properties to extract
const pick = (object, props) => props.reduce((picked, prop) => ({
...picked,
[prop]: object[prop]
}), {})
// we can use `pick` to get only the information we need
const condensedUser = pick(user, ["username", "email"])
// ⇒ {
// username: "clarkkent",
// email: "ckent@dailyplanet.com"
// }// we don’t want to pass all of this information along all the time
const user = {
email: "ckent@dailyplanet.com",
password: "i-am-superman",
username: "clarkkent"
}
// this function receives an object and a list of properties to extract
const pick = (object, props) => props.reduce((picked, prop) => ({
...picked,
[prop]: object[prop]
}), {})
// we can use `pick` to get only the information we need
const condensedUser = pick(user, ["username", "email"])
// ⇒ {
// username: "clarkkent",
// email: "ckent@dailyplanet.com"
// }// we don’t want to pass all of this information along all the time
const user = {
email: "ckent@dailyplanet.com",
password: "i-am-superman",
username: "clarkkent"
}
// this function receives an object and a list of properties to extract
const pick = (object, props) => props.reduce((picked, prop) => ({
...picked,
[prop]: object[prop]
}), {})
// we can use `pick` to get only the information we need
const condensedUser = pick(user, ["username", "email"])
// ⇒ {
// username: "clarkkent",
// email: "ckent@dailyplanet.com"
// }Continue reading
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