implicit return in blocks

src/ndspkg/compiler/scope.nim

@@ -33,6 +33,14 @@ proc beginScope*(comp: Compiler, function: bool = false) =
   for label in scope.labels:
     comp.addLocal(&":{label}", delta = 0)
 
+proc scopeRetIndex*(comp: Compiler): int =
+  let scope = comp.scopes[comp.scopes.high()]
+  when assertionsCompiler:
+    # this is an illegal operation for function scopes, as they work differently
+    if scope.function:
+      comp.error("Assertion failed, Internal error, scopeRetIndex calculation for a function scope.")
+  return scope.goalStackIndex
+
 proc restore*(comp: Compiler, scope: Scope) =
   let delta = comp.stackIndex - scope.goalStackIndex
   comp.writePops(delta)

src/ndspkg/compiler/statement.nim

@@ -51,8 +51,13 @@ proc statement*(comp: Compiler) =
     comp.breakStatement()
   else:
     comp.expression()
+    if comp.current.tokenType == tkRightBrace:
+      # last expression in the block expression -> semicolon optional
+      comp.writeChunk(0, opSetLocal)
+      comp.writeChunk(0, comp.scopeRetIndex().toDU8())
+    else:
+      comp.consume(tkSemicolon, "Semicolon expected after expression statement.")
     comp.writeChunk(-1, opPop)
-    comp.consume(tkSemicolon, "Semicolon expected after expression statement.")
 
   if comp.panicMode:
     comp.synchronize()

tests/closures.nds

@@ -1,27 +1,27 @@
 // cascade
 
-var f1 = funct() { @result
+var f1 = funct() {
   var x = 1;
   var y = 5;
-  :result = funct() { @result
+  funct() {
     var z = 8;
     print (x);
     x = x + 1;
-    :result = funct() { @result
+    funct() {
       print (x);
       x = x + 1;
-      :result = funct() { @result
+      funct() {
         print (x);
         print (y);
         print (z);
         x = x + 1;
-        :result = funct() {
+        funct() {
           print (x);
           x = x + 1;
-        };
-      };
-    };
-  };
+        }
+      }
+    }
+  }
 };
 f1()()()()();
 //expect:1.0
@@ -33,13 +33,13 @@ f1()()()()();
 
 // capturing closures in lists:
 
-var f = funct() { @result
+var f = funct() {
   var y = 5;
   var x = @[
     funct() print (y),
     funct() y = y + 1
   ];
-  :result = x;
+  x
 };
 
 var inst = f();