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3.8.1 Introduction to Memory

CoCoA has three types of memory: working, global, and ring-bound memory. Unlike previous versions of CoCoA, starting with CoCoA 3.5, variables defined during a session are by default assigned to a working memory, accessible from all rings (but not from user-defined functions). There are no longer variables that are local to a particular ring. However, as in previous versions of CoCoA, one may define variables in the global memory by using the prefix MEMORY.

The word global now refers to the fact that these variables are accessible not only to all rings but also to user-defined functions. A special class of global variables can be stored in what is called the ring-bound memory. Most users will never need the ring-bound memory! These variables are formed with the prefix MEMORY.ENV.R where R is a ring identifier; they are bound to the ring, which means that they are automatically destroyed when their corresponding rings cease to exist. Otherwise, variables in the ring-bound memory behave exactly as all other global variables.

These three types of memory are discussed separately, below.