new ctx branch

generator/js_of_ast.ml

@@ -381,3 +381,83 @@ let to_javascript module_name typedtree =
   let pre_res = ppf_module_wrap module_name content in
   (L.logged_output pre_res, L.unlogged_output pre_res, pre_res)
 
+
+
+(*
+ctx_empty
+ctx_push(ctx, bindings)   where bindings = [ { key:"ls", val:ls}, { key:"xs", val:xs } ]
+
+example:  
+  ctx321 = ctx_push(ctx320, bindings); log(|line|, ctx321, "ctx_push")
+
+
+  enter  (or call)   => current ctx plus arguments of the call
+  return (was exit)  => current ctx plus return value
+  let (on the "in")  => current ctx plus new binding
+  case               => current ctx plus bound variables
+ 
+  type token_info = ctx_operation * ctx
+
+  
+  if  ==> viewed as match with case true/false.
+
+
+ctx_empty is passed on each structure_item
+on each ctx extension, we need a fresh name (enter, let, match_branch)
+(for return values, do the extension on the fly)
+
+   
+   return f(x);
+translates as
+   var v213 = f(x);
+   log(|line|, ctx_push(ctx320, {key: "return", val: v213}), "return")
+
+
+
+  match v with | None -> x | Some y -> y
+translates as
+  function() { 
+
+
+  
+----------------------
+  let f ... =
+    match ...
+
+=> 
+  switch
+    case:
+      return;
+
+----------------------
+  let f ... =
+    match .. -> 
+      match ...
+
+=>
+  return
+
+----------------------
+  let x = match ... in ...
+=> 
+  switch ...
+    case:
+      x = ..; break;
+    case:
+      x = ..; break;
+
+
+----------------------
+  let x = 
+    match .. ->
+      match .. ->
+=> 
+  would not work without wrapping
+
+----------------------
+
+  f (match ...)
+=> 
+  requires A-normalization
+
+*)
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generator/tests/testctx.ml

+
+let testa x = 
+  x
+
+let testb x = 
+  let x = x in x
+
+let testc x = 
+  let y = x in 
+  let x = y+1 in
+  x+y
+
+let testd x =
+  let f x = 
+    let y = x in y in
+  f x
+
+let teste x =
+  let y =
+    let z = x in z in
+  y
+
+let testf x =
+  let f a = 
+    let y = a in x+y in
+  f x
+
+
+let testg x =
+  if x then 1 else 0
+
+
+
+
+
+let test0 = 
+  match Some 3 with
+  | None -> 2
+  | Some y -> y
+
+
+let test1 on = 
+  let x = 
+    match on with 
+    | None -> 0
+    | Some n -> n
+    in
+  2*x
+
+let test2 v =
+  let x = 
+    let x = 3 in x+1 
+    in
+  x
+
+
+let test3 x =
+  let x =
+    match x with 
+    | None -> 1
+    | Some x -> x+2
+    in
+  x
+
+let test4 x =
+  let y = x+1 in
+  let x x = x in
+  x (let x = y in x)
+
+let test5 x =
+  match x with
+  | None -> 0
+  | Some x -> let x = x+x in x+1
+
+(*
+
+let test6 = 
+  function z -> match z with (x,y) -> x
+*)
+(*
+let test6 (x,y) =
+  x
+  *)
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