matita/contribs/RELATIONAL/NPlus/defs.ma

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  14
  15
  16
  17 include "datatypes/Nat.ma".
  18
  19 inductive NPlus (p:Nat): Nat \to Nat \to Prop \def
  20    | nplus_zero_2: NPlus p zero p
  21    | nplus_succ_2: \forall q, r. NPlus p q r \to NPlus p (succ q) (succ r).
  22
  23 (*CSC: the URI must disappear: there is a bug now *)
  24 interpretation "natural plus predicate" 'rel_plus x y z =
  25    (cic:/matita/RELATIONAL/NPlus/defs/NPlus.ind#xpointer(1/1) x y z).
  26
  27 notation "hvbox(a break + b break == c)"
  28   non associative with precedence 95
  29 for @{ 'rel_plus $a $b $c}.