Lang: Make comparisons a bit more flexible

fxpl · Oct 24, 2024 · 5e065c8 · 5e065c8
1 parent 4e47453
commit 5e065c8
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Showing 4 changed files with 24 additions and 12 deletions.
diff --git a/src/lang/lang.h b/src/lang/lang.h
@@ -30,12 +30,13 @@ inline const TokenDef Compile{"compile"};
 
 namespace verona::wf
 {
+  inline const auto cond = Eq | Neq;
   inline const auto lv = Ident | Lookup;
-  inline const auto rv = lv | Empty | Null | String | Call | Method | Take;
+  inline const auto rv =
+    lv | Empty | Null | String | Call | Method | Take | cond;
   inline const auto cmp_values = Ident | Lookup | Null | Call | Method;
   inline const auto key = Ident | Lookup | String;
   inline const auto operand = Lookup | Call | Method | Ident;
-  inline const auto cond = Eq | Neq;
 
   inline const auto grouping = (Top <<= File) | (File <<= Body) |
     (Body <<= Block) |
@@ -63,13 +64,13 @@ namespace verona::wf
     (Func <<= Body) | (Label <<= Ident)[Ident];
 }
 
+inline const auto COND = T(Eq, Neq);
 inline const auto LV = T(Ident, Lookup);
 inline const auto RV =
-  T(Empty, Ident, Lookup, Null, String, Call, Method, Take);
+  T(Empty, Ident, Lookup, Null, String, Call, Method, Take, Eq, Neq);
 inline const auto CMP_V = T(Ident, Lookup, Null, Call, Method);
 inline const auto KEY = T(Ident, Lookup, String);
 inline const auto OPERAND = T(Lookup, Call, Method, Ident);
-inline const auto COND = T(Eq, Neq);
 
 // Parsing && AST construction
 Parse parser();

diff --git a/src/lang/passes/grouping.cc b/src/lang/passes/grouping.cc
@@ -62,6 +62,11 @@ PassDef grouping()
               ((T(Group) << (RV[Rhs] * End)) / (RV[Rhs] * End)) * End) >>
         [](auto& _) { return Assign << _[Lhs] << _[Rhs]; },
 
+      // Normalize `if x:` -> `if x == True`
+      In(If, While) * ((T(Group) << End) * (!COND)[Op]) >>
+        [](auto& _) {
+          return Seq << Group << (Eq << _(Op) << (Ident ^ "True"));
+        },
       COND[Op] << (Any[Lhs] * (T(Group) << CMP_V[Rhs] * End) * End) >>
         [](auto& _) {
           return create_from(_(Op)->type(), _(Op)) << _[Lhs] << _[Rhs];
@@ -97,10 +102,6 @@ PassDef grouping()
           return create_from(For, _(For))
             << _(Key) << _(Value) << _(Op) << _(Block);
         },
-      In(While) * ((T(Group) << End) * (!COND)[Op]) >>
-        [](auto& _) {
-          return Seq << Group << (Eq << _(Op) << (Ident ^ "True"));
-        },
       (T(While) << (T(Group) * COND[Op] * (T(Group) << T(Block)[Block]))) >>
         [](auto& _) { return While << _(Op) << _(Block); },
 

diff --git a/src/lang/passes/parse.cc b/src/lang/passes/parse.cc
@@ -10,14 +10,15 @@ namespace verona::wf
     Group | Assign | If | Else | Block | For | Func | List | Return | While;
 
   inline const auto parser = (Top <<= File) | (File <<= parse_groups++) |
-    (Assign <<= Group++) | (If <<= Group * (Op >>= (cond | Group)) * Group) |
+    (Assign <<= Group * (Lhs >>= (Group | cond))) |
+    (If <<= Group * (Op >>= (cond | Group)) * Group) |
     (Else <<= Group * Group) | (Group <<= (parse_tokens | Block | List)++) |
     (Block <<= (parse_tokens | parse_groups)++) | (Eq <<= Group * Group) |
     (Neq <<= Group * Group) | (Lookup <<= Group) |
     (For <<= Group * List * Group * Group) |
     (While <<= Group * (Op >>= (cond | Group)) * Group) | (List <<= Group++) |
     (Parens <<= (Group | List)++) | (Func <<= Group * Group * Group) |
-    (Return <<= Group++);
+    (Return <<= (Group | cond)++);
 }
 
 struct Indent
@@ -34,7 +35,7 @@ trieste::Parse parser()
   indent->push_back({0, File});
 
   auto update_indent = [indent](detail::Make& m, size_t this_indent) {
-    m.term({Assign, Return});
+    m.term({Eq, Neq, Assign, Return});
 
     if (this_indent > indent->back().indent)
     {

diff --git a/tests/exprs/ifs.vpy b/tests/exprs/ifs.vpy
@@ -1,4 +1,3 @@
-
 # Build a region
 a = {}
 a["self"] = a
@@ -21,5 +20,15 @@ else:
         d = {}
         drop d
 
+cond = f.a != a
+if cond:
+    dummy = "created"
+
+def check():
+    c = False
+    return c == True
+if check():
+    this = "is false"
+
 drop a
 drop f