0 used to refer to computer files or memory that can be read or used, but not changed or added to in any way: --
Another form of core memory called core rope memory provided read-only storage.
Initially the computer only had 32 words of storage, and 27 of these words were read-only registers made of toggle switches.
The operating system will be read-only memory-based and as such may only apply to motherboards which have this operating system embedded.
This then leaves two categorical constructions to account for: they are needed to model the generalisation from one-way to two-way machines, and from read-only machines to read/write machines.
The important notion in this example is the following data flow: the input is first processed read-only, creating an aliased piece of data, namely the "best" element.
The points of re-use are determined by three usage aspects that characterise variable usages as destructive (aspect 1), read-only shared (aspect 2) and read-only unshared (aspect 3).
A subtyping relation, allows us to treat store cells as either read-write, read-only, or write-only.
The aspects are (1) used destructively, (2), used read-only but shared with result, and (3) used read-only and not shared with the result.
