Looking at this TypeScript code snippet:
const arr: ReadonlyArray<string> = [
"123",
"234"
];
arr.push("345");
An error is thrown by the TS compiler:
.Property 'push' does not exist on type 'ReadonlyArray<string>'
It's evident that the array cannot be modified. So, the question arises: what is the parent class of ReadonlyArray? Is it derived from the standard Array class?
Visit this link
to learn about TypeScript's ReadonlyArray<T> type which ensures your arrays remain unchanged after creation.
TypeScript provides a
ReadonlyArray<T>type that is similar toArray<T>, but without any methods for mutation, allowing you to safeguard the integrity of your arrays.
To access the source code, go to:
this GitHub page (01.06.2022) - Look for "ReadonlyArray" if there have been updates to the source file.
(the definition can be found on line 1121 in the current version).
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