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Published 20 hours ago • verified publisher icon amnh

Add a Cost type

Open recursion-ninja opened this issue 5 years ago • 1 comments

Currently, our "cost" type is a Double or a new-typed Double labeled ExtendedReal.

Our use-case for Cost does not overlap well with the Num and related "numeric" type-class instances.

Our Cost should have the following invariants:

  • Non-negative
  • Monotonically non-decreasing "addition"
  • Equatable
  • Total ordering
  • An "infinite value" representation
  • Perfect precision for rational numbers
  • Reasonable efficiency

We could represent Cost as a non-negative rational number and a Monoid under addition.

recursion-ninja avatar Apr 25 '19 18:04 recursion-ninja