1 files changed, 26 insertions, 0 deletions
diff --git a/theories/Num/Nat/NSyntax.v b/theories/Num/Nat/NSyntax.v
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+++ b/theories/Num/Nat/NSyntax.v
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+
+(*s Syntax for arithmetic *)
+
+Infix 6 "<" lt.
+Infix 6 "<=" le.
+Infix 6 ">" gt.
+Infix 6 ">=" ge.
+
+(*i Infix 7 "+" plus. i*)
+
+Grammar constr lassoc_constr4 :=
+  squash_sum
+  [ lassoc_constr4($c1) "+" lassoc_constr4($c2) ] ->
+      case [$c2] of
+        (SQUASH $T2) ->
+            case [$c1] of
+              (SQUASH $T1) -> [ (sumbool $T1 $T2) ] (* {T1}+{T2} *)
+            | $_           -> [ (sumor $c1 $T2) ]   (* c1+{T2} *)
+            esac
+      | $_           -> [ (add $c1 $c2) ]           (* c1+c2 *)
+      esac.
+
+Syntax constr
+  level 4:
+    sum [ (add $t1 $t2) ] -> [ [<hov 0> $t1:E [0 1] "+" $t2:L ] ]
+.
+\ No newline at end of file