Data structures are an integral part of computers used for the arrangement of data in memory.

A data model can sometimes be referred to as a data structure, especially in the context of programming languages.

okay so remind you what is a sheath so a sheep is something that allows me to 00:05:37 translate between physical sources or physical realms of data and physical regions so these are various 00:05:49 open sets or translation between them by taking a look at restrictions overlaps 00:06:02 and then inferring

Purely functional data structures are persistent. Persistency is required for functional programming; without it, the same computation could return different results.

We could change the definition of Cons to hold references instead, but then we would have to specify lifetime parameters. By specifying lifetime parameters, we would be specifying that every element in the list will live at least as long as the entire list. The borrow checker wouldn’t let us compile let a = Cons(10, &Nil); for example, because the temporary Nil value would be dropped before a could take a reference to it.

In graph theory, a tree is a connected acyclic graph; unless stated otherwise, in graph theory trees and graphs are assumed undirected. There is no one-to-one correspondence between such trees and trees as data structure.

Yet, for all the seeming convenience of Microsoft Excel (and its ilk), we pay a hefty price — our time and sanity. “Hyperbole!” I hear you shout. “Nonsense!” I hear you cry. And, when these initial protestations fade, we are left with the ever popular: “I have a system.”