[TYPES] What algebra am I thinking of?

[ The Types Forum, http://lists.seas.upenn.edu/mailman/listinfo/types-list ]

Consider a blockchain managing several different resources. Over time, new
resources may be added or deleted. Each input to or output from a
transaction is associated with a value, where each value consists of
associating zero or more resources with amounts, where the amounts are
natural numbers (that is, integers greater than or equal to zero).

What kind of algebra do values correspond to? It seems similar to vector
spaces, except:
  (a) adding or deleting resources increases or decreases the number of
dimensions in the vector space
  (b) the scalars in the vector space are natural numbers rather than reals

What algebra am I thinking of? Cheers, -- P


.   \ Philip Wadler, Professor of Theoretical Computer Science,
.   /\ School of Informatics, University of Edinburgh
.  /  \ and Senior Research Fellow, IOHK
. http://homepages.inf.ed.ac.uk/wadler/

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