Spec changed; Changes introduced; fixed minor bugs

Changes

@@ -0,0 +1,20 @@
+LaMa 1.10
+---------
+
+Version 1.10 clears some inconsistnces in 1.00. The language is *not* top-down compatible
+with 1.00, but the conversion is simple.
+
+# Language features:
+
+- Removed keywords: local, repeat, until, boxed, unboxed, length, string;
+- Added keywords: var, val, box;
+- local variable declarations syntax changed: local x... -> var x...;
+- repeat ... until syntax changed: now do .. while .. od. Note the inversion in
+  the condition while converting from repeat... to do..while...;
+- .length and .string are now regular functions; hence a conventional synax string (x) and
+  length (x) is possible;
+- pattern syntax changed: #boxed -> #box, #unboxed -> #val, #string -> #str;
+- scope expressions are integrated with ( ... ) primaries; thus,
+  nested scopes are introduced with *round* brackets;
+- no more List.singleton is needed since there is no more confilict between one-element lists
+  and scoped expressions.

src/X86.ml

@@ -229,11 +229,11 @@ let compile cmd env imports code =
     | [] -> env, []
     | instr :: scode' ->
         let stack = "" (* env#show_stack*) in
-        (* Printf.printf "insn=%s, stack=%s\n%!" (GT.show(insn) instr) (env#show_stack);  *)
+        (* Printf.printf "insn=%s, stack=%s\n%!" (GT.show(insn) instr) (env#show_stack);   *)
         let env', code' =
           if env#is_barrier
           then match instr with
-               | LABEL  s -> if env#has_stack s then (env#drop_barrier)#retrieve_stack s, [Label s] else env, []
+               | LABEL  s -> if env#has_stack s then (env#drop_barrier)#retrieve_stack s, [Label s] else env#drop_stack, []
                | FLABEL s -> env#drop_barrier, [Label s]
                | SLABEL s -> env, [Label s]
                | _        -> env, []
@@ -629,11 +629,14 @@ class env prg =
     method is_barrier = barrier
 
     (* set barrier *)
-    method set_barrier = {< stack = []; barrier = true >}
+    method set_barrier = {< barrier = true >}
 
     (* drop barrier *)
     method drop_barrier = {< barrier = false >}
 
+    (* drop stack *)
+    method drop_stack = {< stack = [] >}
+
     (* associates a stack to a label *)
     method set_stack l = (*Printf.printf "Setting stack for %s\n" l;*)
       {< stackmap = M.add l stack stackmap >}

src/version.ml

@@ -1 +1 @@
-let version = "Version 1.10, f1430a1cd, Sun Jan 31 22:57:12 2021 +0300"
+let version = "Version 1.10, 7c7ef67e1, Mon Feb 1 09:52:28 2021 +0300"

tutorial/Expressions.lama

@@ -1,15 +1,16 @@
-printf ("if, case, for, while, repeat etc. are all expressions.\n");
+printf ("if, case, for, while etc. are all expressions.\n");
 
 printf ("Case-expression: %s\n", case A (1, 2, 3) of A (x, y, z) -> z esac.string);
 
 printf ("If-expression: %s\n", (if true then 2 else 3 fi +
                                if false then 6 else 7 fi).string);
-                               
-printf ("Scope-expression: %s\n", {local i, s = 0;
+
+printf ("Scope-expression: %s\n", (var i, s = 0;
                                    for i := 0, i < 10, i := i + 1 do
                                      s := s + i
                                    od;
                                    s
-                                  }.string
+                                  ).string
        )
+       
 

tutorial/PatternMatching.lama

@@ -1,21 +1,23 @@
 fun show (x) {
   fun show (level, x) {
-    for local i; i := 0, i<level, i := i + 1 do
+    for var i; i := 0, i<level, i := i + 1 do
       printf (" ")
     od;
   
     case x of
-      #unboxed -> printf ("integer %d\n", x);
-                  return                
-    | #array   -> printf ("array\n")
-    | #string  -> printf ("string\n")
-    | #sexp    -> printf ("S-expression\n")
-    | #fun     -> printf ("closure 0x%x\n", x[0])
+      #val   -> printf ("integer %d\n", x)
+    | #array -> printf ("array\n")
+    | #str   -> printf ("string\n")
+    | #sexp  -> printf ("S-expression\n")
+    | #fun   -> printf ("closure 0x%x\n", x[0])
     esac;
 
-    for local i; i := case x of #fun -> 1 | _ -> 0 esac, i < x.length, i := i + 1 do
-      show (level + 2, x[i])
-    od
+    case x of
+      #val -> skip
+    | _    -> for var i; i := case x of #fun -> 1 | _ -> 0 esac, i < x.length, i := i + 1 do
+                show (level + 2, x[i])
+              od
+    esac
   }
 
   show (0, x)

tutorial/Values.lama

@@ -1,18 +1,18 @@
-local samples = [
+var samples = [
   {"a", "b", "c"},
   "string",
   [],
   Fruit ("apple"),
-  fun (){skip}
+  fun () {skip}
 ];
 
 fun show () {
   -- Note: it would be much better to use iterArray from standard unit Array;
   -- in that case, however, we wouldn't be able to showcase
   -- for-loops and []-expressions.
-  for local i; i := 0, i < samples.length, i := i+1 do
+  for var i; i := 0, i < samples.length, i := i+1 do
     printf ("  %s has %d subvalue(s):\n", samples[i].string, samples[i].length);
-    for local j; j := 0, j < samples[i].length, j := j+1 do
+    for var j; j := 0, j < samples[i].length, j := j+1 do
       printf ("    subvalue [%d] = %s\n", j, samples[i][j].string)
     od
   od
@@ -29,5 +29,5 @@ printf ("And the subvalues of a composite value can be reassigned.\n");
 samples [2]    := [1, 2, 3];
 samples [0][1] := {};
 
-show ()
+show ()