natural numbers

tests/TermImpls.idr

@@ -51,6 +51,15 @@ mutual
     DLam body1 == DLam body2 = body1.term == body2.term
     DLam {} == _ = False
 
+    Nat == Nat = True
+    Nat == _ = False
+
+    Zero == Zero = True
+    Zero == _ = False
+
+    Succ m == Succ n = m == n
+    Succ _ == _ = False
+
     E e == E f = e == f
     E _ == _ = False
 
@@ -85,6 +94,11 @@ mutual
       q1 == q2 && t1 == t2 && r1.term == r2.term && a1 == a2
     CaseEnum {} == _ = False
 
+    CaseNat q1 q1' n1 r1 z1 s1 == CaseNat q2 q2' n2 r2 z2 s2 =
+      q1 == q2 && q1' == q2' && n1 == n2 &&
+      r1.term == r2.term && z1 == z2 && s1.term == s2.term
+    CaseNat {} == _ = False
+
     (fun1 :% dim1) == (fun2 :% dim2) = fun1 == fun2 && dim1 == dim2
     (_ :% _) == _ = False
 

tests/Tests/Parser.idr

@@ -224,6 +224,15 @@ tests = "parser" :- [
     parseFails term "≡"
   ],
 
+  "naturals" :- [
+    parsesAs term "ℕ" Nat,
+    parsesAs term "Nat" Nat,
+    parsesAs term "zero" Zero,
+    parsesAs term "succ n" (Succ $ V "n"),
+    parsesAs term "3" (Succ (Succ (Succ Zero)) :# Nat),
+    parseFails term "succ"
+  ],
+
   "case" :- [
     parsesAs term
       "case1 f s return x ⇒ A x of { (l, r) ⇒ add l r }" $
@@ -251,7 +260,15 @@ tests = "parser" :- [
     parsesAs term "caseω t return A of {}" $
       Case Any (V "t") (Nothing, V "A") (CaseEnum []),
     parsesAs term "case# t return A of {}" $
-      Case Any (V "t") (Nothing, V "A") (CaseEnum [])
+      Case Any (V "t") (Nothing, V "A") (CaseEnum []),
+    parsesAs term "caseω n return A of { 0 ⇒ a; succ n' ⇒ b }" $
+      Case Any (V "n") (Nothing, V "A") $
+        CaseNat (V "a") (Just "n'", Zero, Nothing, V "b"),
+    parsesAs term "caseω n return ℕ of { succ _ [1.ih] ⇒ ih; zero ⇒ 0; }" $
+      Case Any (V "n") (Nothing, Nat) $
+        CaseNat (Zero :# Nat) (Nothing, One, Just "ih", V "ih"),
+    parseFails term "caseω n return A of { zero ⇒ a }",
+    parseFails term "caseω n return ℕ of { succ ⇒ 5 }"
   ],
 
   "definitions" :- [

tests/Tests/Typechecker.idr

@@ -363,6 +363,18 @@ tests = "typechecker" :- [
       check_ empty01 sone (Tag "a") (enum ["b", "c"])
   ],
 
+  "enum matching" :- [
+    testTC "ω.x : {tt} ⊢ 1 · case1 x return {tt} of { 'tt ⇒ 'tt } ⇒ {tt}" $
+      inferAs (ctx [< ("x", enum ["tt"])]) sone
+        (CaseEnum One (BV 0) (SN (enum ["tt"])) $
+          singleton "tt" (Tag "tt"))
+        (enum ["tt"]),
+    testTCFail "ω.x : {tt} ⊢ 1 · case1 x return {tt} of { 'ff ⇒ 'tt } ⇏" $
+      infer_ (ctx [< ("x", enum ["tt"])]) sone
+        (CaseEnum One (BV 0) (SN (enum ["tt"])) $
+          singleton "ff" (Tag "tt"))
+  ],
+
   "equalities" :- [
     testTC "1 · (δ i ⇒ a) ⇐ a ≡ a" $
       check_ empty sone (DLam $ SN $ FT "a")