scope: create two escapemaks in loops

[nit.git] / src / semantize / scope.nit

diff --git a/src/semantize/scope.nit b/src/semantize/scope.nit
index 30aade4..00702d0 100644 (file)
--- a/src/semantize/scope.nit
+++ b/src/semantize/scope.nit
@@ -50,15 +50,12 @@ class EscapeMark
        # The name of the label (unless the mark is an anonymous loop mark)
        var name: nullable String
 
-       # Is the mark attached to a loop (loop, while, for)
-       # Such a mark is a candidate to a labelless 'continue' or 'break'
-       var for_loop: Bool
+       # The associated `continue` mark, if any.
+       # If the mark attached to a loop (loop, while, for), a distinct mark is used.
+       private var continue_mark: nullable EscapeMark = null
 
-       # Each 'continue' attached to the mark
-       var continues = new Array[AContinueExpr]
-
-       # Each 'break' attached to the mark
-       var breaks = new Array[ABreakExpr]
+       # Each break/continue attached to the mark
+       var escapes = new Array[AEscapeExpr]
 end
 
 # Visit a npropdef and:
@@ -81,7 +78,7 @@ private class ScopeVisitor
        end
 
        # All stacked scope. `scopes.first` is the current scope
-       private var scopes = new List[Scope]
+       var scopes = new List[Scope]
 
        # Shift and check the last scope
        fun shift_scope
@@ -176,7 +173,8 @@ private class ScopeVisitor
                else
                        name = null
                end
-               var res = new EscapeMark(name, for_loop)
+               var res = new EscapeMark(name)
+               if for_loop then res.continue_mark = new EscapeMark(name)
                return res
        end
 
@@ -303,10 +301,12 @@ redef class AContinueExpr
                super
                var escapemark = v.get_escapemark(self, self.n_label)
                if escapemark == null then return # Skip error
-               if not escapemark.for_loop then
+               escapemark = escapemark.continue_mark
+               if escapemark == null then
                        v.error(self, "Error: cannot 'continue', only 'break'.")
+                       return
                end
-               escapemark.continues.add(self)
+               escapemark.escapes.add(self)
                self.escapemark = escapemark
        end
 end
@@ -317,19 +317,20 @@ redef class ABreakExpr
                super
                var escapemark = v.get_escapemark(self, self.n_label)
                if escapemark == null then return # Skip error
-               escapemark.breaks.add(self)
+               escapemark.escapes.add(self)
                self.escapemark = escapemark
        end
 end
 
 
 redef class ADoExpr
-       # The escape mark associated with the 'do' block
-       var escapemark: nullable EscapeMark
+       # The break escape mark associated with the 'do' block
+       var break_mark: nullable EscapeMark
+
        redef fun accept_scope_visitor(v)
        do
-               self.escapemark = v.make_escape_mark(n_label, false)
-               v.enter_visit_block(n_block, self.escapemark)
+               self.break_mark = v.make_escape_mark(n_label, false)
+               v.enter_visit_block(n_block, self.break_mark)
        end
 end
 
@@ -343,24 +344,34 @@ redef class AIfExpr
 end
 
 redef class AWhileExpr
-       # The escape mark associated with the 'while'
-       var escapemark: nullable EscapeMark
+       # The break escape mark associated with the 'while'
+       var break_mark: nullable EscapeMark
+
+       # The continue escape mark associated with the 'while'
+       var continue_mark: nullable EscapeMark
+
        redef fun accept_scope_visitor(v)
        do
                var escapemark = v.make_escape_mark(n_label, true)
-               self.escapemark = escapemark
+               self.break_mark = escapemark
+               self.continue_mark = escapemark.continue_mark
                v.enter_visit(n_expr)
                v.enter_visit_block(n_block, escapemark)
        end
 end
 
 redef class ALoopExpr
-       # The escape mark associated with the 'loop'
-       var escapemark: nullable EscapeMark
+       # The break escape mark associated with the 'loop'
+       var break_mark: nullable EscapeMark
+
+       # The continue escape mark associated with the 'loop'
+       var continue_mark: nullable EscapeMark
+
        redef fun accept_scope_visitor(v)
        do
                var escapemark = v.make_escape_mark(n_label, true)
-               self.escapemark = escapemark
+               self.break_mark = escapemark
+               self.continue_mark = escapemark.continue_mark
                v.enter_visit_block(n_block, escapemark)
        end
 end
@@ -369,8 +380,11 @@ redef class AForExpr
        # The automatic variables in order
        var variables: nullable Array[Variable]
 
-       # The escape mark associated with the 'for'
-       var escapemark: nullable EscapeMark
+       # The break escape mark associated with the 'for'
+       var break_mark: nullable EscapeMark
+
+       # The continue escape mark associated with the 'for'
+       var continue_mark: nullable EscapeMark
 
        redef fun accept_scope_visitor(v)
        do
@@ -389,7 +403,8 @@ redef class AForExpr
                end
 
                var escapemark = v.make_escape_mark(n_label, true)
-               self.escapemark = escapemark
+               self.break_mark = escapemark
+               self.continue_mark = escapemark.continue_mark
                v.enter_visit_block(n_block, escapemark)
 
                v.shift_scope