Add and append HTML elements in React

Append arr2 elements to arr: (8) [{…}, {…}, {…}, {…}, {…}, {…}, {…}, {…}]

(arr) => arr.concat(gerArr2())

Append arr2 array to arr: (4) [Array(4), Array(4), Array(4), Array(4)]

(arr) => [...arr, gerArr2()]

Save search term state to React Hooks with spread operator and wrapper function

// Using .concat(), no wrapper function (not recommended)

setSearches(searches.concat(query))

// Using .concat(), wrapper function (recommended)

setSearches(searches => searches.concat(query))

// Spread operator, no wrapper function (not recommended)

setSearches([...searches, query])

// Spread operator, wrapper function (recommended)

setSearches(searches => [...searches, query])

https://stackoverflow.com/questions/54676966/push-method-in-react-hooks-usestate

https://javascript.plainenglish.io/how-to-add-to-an-array-in-react-state-3d08ddb2e1dc

https://www.skptricks.com/2018/06/append-or-prepend-html-using-reactjs.html