helm/software/matita/contribs/RELATIONAL/BEq/defs.ma

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  14
  15 set "baseuri" "cic:/matita/RELATIONAL/BEq/defs".
  16
  17 include "logic/equality.ma".
  18
  19 include "Bool/defs.ma".
  20
  21 inductive BEq (A:Type) (a1:A): A \to Bool \to Prop \def
  22    | beq_true : BEq A a1 a1 true
  23    | beq_false: \forall a2. (a1 = a2 -> False) \to BEq A a1 a2 false
  24 .
  25
  26 (*CSC: the URI must disappear: there is a bug now *)
  27 interpretation "boolean equality" 'beq x y z =
  28    (cic:/matita/RELATIONAL/BEq/defs/BEq.ind#xpointer(1/1) _ x y z).
  29
  30 notation "hvbox(a break -- b break == c)"
  31   non associative with precedence 95
  32 for @{ 'beq $a $b $c}.