;;;; levenshtein-cost-number.scm -*- Scheme -*-
;;;; Kon Lovett, Mar '20
;;;; Kon Lovett, Apr '12
;;;; Kon Lovett, May '06

(include "levenshtein-cost-interface")

(module levenshtein-cost-number COST-OPER

(import scheme)
(import (chicken base))
(import (chicken type))

(define-type cost number)

(: cost-multiply (cost cost -> cost))
(: cost-add (cost cost -> cost))
(: cost-minimum (cost #!rest cost -> cost))
(: cost-less-than (cost cost -> boolean))
(define-type cost-positive-infinity cost)

(define cost-add +)
(define cost-multiply *)
(define cost-minimum min)
(define cost-less-than <)
(define cost-positive-infinity +inf.0)

) ;module levenshtein-cost-number