tco

parse.cm

@@ -1425,7 +1425,9 @@ var parse = function(tokens, src, filename, tokenizer) {
       vars: [],
       in_loop: opts.in_loop == true,
       function_nr: fn_nr,
-      is_function_scope: opts.is_func == true
+      is_function_scope: opts.is_func == true,
+      func_node: null,
+      has_inner_func: false
     }
   }
 
@@ -1478,6 +1480,15 @@ var parse = function(tokens, src, filename, tokenizer) {
     return false
   }
 
+  var sem_find_func_scope = function(scope) {
+    var s = scope
+    while (s != null) {
+      if (s.is_function_scope) return s
+      s = s.parent
+    }
+    return null
+  }
+
   var sem_add_intrinsic = function(name) {
     if (find(intrinsics, name) == null) push(intrinsics, name)
   }
@@ -1635,6 +1646,7 @@ var parse = function(tokens, src, filename, tokenizer) {
     var pname = null
     var def_val = null
     var sr = null
+    var enclosing = null
 
     if (_assign_kinds[kind] == true) {
       sem_check_assign_target(scope, expr.left)
@@ -1736,9 +1748,12 @@ var parse = function(tokens, src, filename, tokenizer) {
     }
 
     if (kind == "function") {
+      enclosing = sem_find_func_scope(scope)
+      if (enclosing != null) enclosing.has_inner_func = true
       fn_nr_val = expr.function_nr
       if (fn_nr_val == null) fn_nr_val = scope.function_nr
       fn_scope = make_scope(scope, fn_nr_val, {is_func: true})
+      fn_scope.func_node = expr
       expr.outer = scope.function_nr
       i = 0
       while (i < length(expr.list)) {
@@ -1819,6 +1834,8 @@ var parse = function(tokens, src, filename, tokenizer) {
     var pname = null
     var def_val = null
     var sr = null
+    var enclosing = null
+    var func_scope = null
     var tt = null
 
     if (kind == "var_list") {
@@ -1941,7 +1958,26 @@ var parse = function(tokens, src, filename, tokenizer) {
       return null
     }
 
-    if (kind == "return" || kind == "go") {
+    if (kind == "go") {
+      sem_check_expr(scope, stmt.expression)
+      if (stmt.expression == null || stmt.expression.kind != "(") {
+        sem_error(stmt, "'go' must be followed by a function call")
+      } else {
+        func_scope = sem_find_func_scope(scope)
+        if (func_scope != null && func_scope.func_node != null) {
+          if (func_scope.func_node.disruption != null) {
+            sem_error(stmt, "cannot use 'go' in a function with a disruption clause")
+          }
+          if (func_scope.has_inner_func) {
+            sem_error(stmt, "cannot use 'go' in a function that defines inner functions")
+          }
+        }
+        stmt.tail = true
+      }
+      return null
+    }
+
+    if (kind == "return") {
       sem_check_expr(scope, stmt.expression)
       if (stmt.expression != null && stmt.expression.kind == "(") {
         stmt.tail = true
@@ -1982,11 +2018,14 @@ var parse = function(tokens, src, filename, tokenizer) {
     }
 
     if (kind == "function") {
+      enclosing = sem_find_func_scope(scope)
+      if (enclosing != null) enclosing.has_inner_func = true
       name = stmt.name
       if (name != null) sem_add_var(scope, name, {make: "function", fn_nr: scope.function_nr})
       fn_nr_val = stmt.function_nr
       if (fn_nr_val == null) fn_nr_val = scope.function_nr
       fn_scope = make_scope(scope, fn_nr_val, {is_func: true})
+      fn_scope.func_node = stmt
       stmt.outer = scope.function_nr
       i = 0
       while (i < length(stmt.list)) {