Merge branch 'master' of https://github.com/redbrain/gccrs

3 files changed, 515 insertions, 16 deletions

diff --git a/gcc/rust/analysis/rust-type-resolution.cc b/gcc/rust/analysis/rust-type-resolution.cc
index 3e2db7f..f1edec8 100644
--- a/gcc/rust/analysis/rust-type-resolution.cc
+++ b/gcc/rust/analysis/rust-type-resolution.cc
@@ -1,5 +1,6 @@
 #include "rust-type-resolution.h"
 #include "rust-diagnostics.h"
+#include "rust-type-visitor.h"
 
 #define ADD_BUILTIN_TYPE(_X, _S)                                               \
   do                                                                           \
@@ -104,7 +105,13 @@ TypeResolution::typesAreCompatible (AST::Type *lhs, AST::Type *rhs,
     }
 
   AST::Type *val = NULL;
-  return scope.LookupType (lhsTypeStr, &val);
+  if (!scope.LookupType (lhsTypeStr, &val))
+    {
+      rust_error_at (locus, "Unknown type: %s", lhsTypeStr.c_str ());
+      return false;
+    }
+
+  return true;
 }
 
 bool
@@ -395,19 +402,133 @@ TypeResolution::visit (AST::CompoundAssignmentExpr &expr)
 void
 TypeResolution::visit (AST::GroupedExpr &expr)
 {}
-// void TypeResolution::visit(ArrayElems& elems) {}
+
 void
 TypeResolution::visit (AST::ArrayElemsValues &elems)
-{}
+{
+  // we need to generate the AST::ArrayType for this array init_expression
+  // we can get the size via get_num_values() but we need to ensure each element
+  // are type compatible
+
+  bool failed = false;
+  AST::Type *last_inferred_type = nullptr;
+  elems.iterate ([&] (AST::Expr *expr) mutable -> bool {
+    size_t before;
+    before = typeBuffer.size ();
+    expr->accept_vis (*this);
+    if (typeBuffer.size () <= before)
+      {
+	rust_error_at (expr->get_locus_slow (),
+		       "unable to determine element type");
+	return false;
+      }
+
+    AST::Type *inferedType = typeBuffer.back ();
+    typeBuffer.pop_back ();
+
+    if (last_inferred_type == nullptr)
+      last_inferred_type = inferedType;
+    else
+      {
+	if (!typesAreCompatible (last_inferred_type, inferedType,
+				 expr->get_locus_slow ()))
+	  {
+	    failed = true;
+	    return false;
+	  }
+      }
+
+    return true;
+  });
+
+  // nothing to do when its failed
+  if (failed)
+    return;
+
+  // FIXME This will leak
+  auto capacity
+    = new AST::LiteralExpr (std::to_string (elems.get_num_values ()),
+			    AST::Literal::INT,
+			    Linemap::predeclared_location ());
+  auto arrayType = new AST::ArrayType (last_inferred_type->clone_type (),
+				       std::unique_ptr<AST::Expr> (capacity),
+				       Linemap::predeclared_location ());
+  typeBuffer.push_back (arrayType);
+}
+
 void
 TypeResolution::visit (AST::ArrayElemsCopied &elems)
-{}
+{
+  printf ("ArrayElemsCopied: %s\n", elems.as_string ().c_str ());
+}
+
 void
 TypeResolution::visit (AST::ArrayExpr &expr)
-{}
+{
+  auto& elements = expr.get_array_elems ();
+
+  auto before = typeBuffer.size ();
+  elements->accept_vis (*this);
+  if (typeBuffer.size () <= before)
+    {
+      rust_error_at (expr.get_locus_slow (),
+		     "unable to determine type for ArrayExpr");
+      return;
+    }
+
+  expr.set_inferred_type (typeBuffer.back ());
+}
+
 void
 TypeResolution::visit (AST::ArrayIndexExpr &expr)
-{}
+{
+  auto before = typeBuffer.size ();
+  expr.get_array_expr ()->accept_vis (*this);
+  if (typeBuffer.size () <= before)
+    {
+      rust_error_at (expr.get_locus_slow (),
+		     "unable to determine type for array index expression");
+      return;
+    }
+  AST::Type *array_expr_type = typeBuffer.back ();
+  typeBuffer.pop_back ();
+
+  before = typeBuffer.size ();
+  expr.get_index_expr ()->accept_vis (*this);
+  if (typeBuffer.size () <= before)
+    {
+      rust_error_at (expr.get_index_expr ()->get_locus_slow (),
+		     "unable to determine type for index expression");
+      return;
+    }
+
+  AST::Type *array_index_type = typeBuffer.back ();
+  typeBuffer.pop_back ();
+
+  // check the index_type should be an i32 which should really be
+  // more permissive
+  AST::Type *i32 = nullptr;
+  scope.LookupType ("i32", &i32);
+  rust_assert (i32 != nullptr);
+
+  if (!typesAreCompatible (array_index_type, i32,
+			   expr.get_index_expr ()->get_locus_slow ()))
+    {
+      return;
+    }
+
+  // the the element type from the array_expr_type and it _must_ be an array
+  AST::ArrayType *resolved = ArrayTypeVisitor::Resolve (array_expr_type);
+  if (resolved == nullptr)
+    {
+      rust_error_at (expr.get_locus_slow (),
+		     "unable to resolve type for array expression");
+      return;
+    }
+
+  typeBuffer.push_back (resolved->get_elem_type ().get ());
+}
+
 void
 TypeResolution::visit (AST::TupleExpr &expr)
 {}
@@ -516,6 +637,10 @@ TypeResolution::visit (AST::StructExprStructFields &expr)
 	}
     }
 
+  // need to correct the ordering with the respect to the struct definition and
+  // ensure we handle missing values and give them defaults
+  // FIXME
+
   // setup a path in type
   AST::PathIdentSegment seg (expr.get_struct_name ().as_string ());
   auto typePath = ::std::unique_ptr<AST::TypePathSegment> (
@@ -649,9 +774,42 @@ TypeResolution::visit (AST::RangeFromToInclExpr &expr)
 void
 TypeResolution::visit (AST::RangeToInclExpr &expr)
 {}
+
 void
 TypeResolution::visit (AST::ReturnExpr &expr)
-{}
+{
+  // Ensure the type of this matches the function
+  auto before = typeBuffer.size ();
+  expr.get_returned_expr ()->accept_vis (*this);
+
+  if (typeBuffer.size () <= before)
+    {
+      rust_error_at (expr.get_returned_expr ()->get_locus_slow (),
+		     "unable to determine type for return expr");
+      return;
+    }
+
+  auto inferedType = typeBuffer.back ();
+  typeBuffer.pop_back ();
+
+  // check this is compatible with the return type
+  // this will again have issues with structs before we move to HIR
+
+  auto function = scope.CurrentFunction ();
+  if (!function->has_return_type ())
+    {
+      rust_error_at (expr.get_locus (), "return for void function %s",
+		     function->as_string ().c_str ());
+      return;
+    }
+
+  if (!typesAreCompatible (function->get_return_type ().get (), inferedType,
+			   expr.get_locus_slow ()))
+    {
+      return;
+    }
+}
+
 void
 TypeResolution::visit (AST::UnsafeBlockExpr &expr)
 {}
@@ -764,18 +922,26 @@ TypeResolution::visit (AST::Function &function)
   // its  a marker for a void function
   scope.InsertType (function.get_function_name (), function.get_return_type ().get ());
   scope.InsertFunction (function.get_function_name (), &function);
+  scope.PushFunction (&function);
   scope.Push ();
 
   for (auto &param : function.get_function_params ())
     {
       if (!isTypeInScope (param.get_type ().get (), param.get_locus ()))
-	return;
+	{
+	  scope.Pop ();
+	  scope.PopFunction ();
+	  return;
+	}
 
       auto before = letPatternBuffer.size ();
       param.get_pattern ()->accept_vis (*this);
       if (letPatternBuffer.size () <= before)
 	{
 	  rust_error_at (param.get_locus (), "failed to analyse parameter name");
+
+	  scope.Pop ();
+	  scope.PopFunction ();
 	  return;
 	}
 
@@ -788,7 +954,11 @@ TypeResolution::visit (AST::Function &function)
   if (function.has_return_type ())
     {
       if (!isTypeInScope (function.get_return_type ().get (), function.get_locus ()))
-	return;
+	{
+	  scope.Pop ();
+	  scope.PopFunction ();
+	  return;
+	}
     }
 
   // walk the expression body
@@ -802,6 +972,7 @@ TypeResolution::visit (AST::Function &function)
     function.locals.push_back (value);
 
   scope.Pop ();
+  scope.PopFunction ();
 }
 
 void
@@ -1011,7 +1182,7 @@ TypeResolution::visit (AST::LetStmt &stmt)
       return;
     }
 
-  AST::Type *inferedType = NULL;
+  AST::Type *inferedType = nullptr;
   if (stmt.has_init_expr ())
     {
       auto before = typeBuffer.size ();
@@ -1044,13 +1215,51 @@ TypeResolution::visit (AST::LetStmt &stmt)
 	  return;
 	}
     }
-  else if (stmt.has_type () && !stmt.has_init_expr ())
+  else if (stmt.has_type ())
     {
-      inferedType = stmt.get_type ().get ();
+      auto before = typeComparisonBuffer.size ();
+      stmt.get_type ()->accept_vis (*this);
+      if (typeComparisonBuffer.size () <= before)
+	{
+	  rust_error_at (stmt.get_locus (), "failed to understand type for lhs");
+	  return;
+	}
+      auto typeString = typeComparisonBuffer.back ();
+      typeComparisonBuffer.pop_back ();
+
+      // AST::Type *val = NULL;
+      // if (!scope.LookupType (typeString, &val))
+      //   {
+      //     rust_error_at (stmt.locus, "LetStmt has unknown type: %s",
+      //   		 stmt.type->as_string ().c_str ());
+      //     return;
+      //   }
+    }
+  else if (inferedType != nullptr)
+    {
+      auto before = typeComparisonBuffer.size ();
+      inferedType->accept_vis (*this);
+      if (typeComparisonBuffer.size () <= before)
+	{
+	  rust_error_at (stmt.get_locus (), "failed to understand type for lhs");
+	  return;
+	}
+      auto typeString = typeComparisonBuffer.back ();
+      typeComparisonBuffer.pop_back ();
+
+      // AST::Type *val = NULL;
+      // if (!scope.LookupType (typeString, &val))
+      //   {
+      //     rust_error_at (stmt.get_locus (), "Inferred unknown type: %s",
+      //   		 inferedType->as_string ().c_str ());
+      //     return;
+      //   }
+    }
+  else
+    {
+      rust_fatal_error (stmt.get_locus (), "Failed to determine any type for LetStmt");
+      return;
     }
-
-  // TODO check we know what the type is in the scope requires the builtins to
-  // be defined at the constructor
 
   // ensure the decl has the type set for compilation later on
   if (!stmt.has_type ())
@@ -1118,9 +1327,13 @@ TypeResolution::visit (AST::RawPointerType &type)
 void
 TypeResolution::visit (AST::ReferenceType &type)
 {}
+
 void
 TypeResolution::visit (AST::ArrayType &type)
-{}
+{
+  typeComparisonBuffer.push_back (type.get_elem_type ()->as_string ());
+}
+
 void
 TypeResolution::visit (AST::SliceType &type)
 {}
diff --git a/gcc/rust/analysis/rust-type-resolution.h b/gcc/rust/analysis/rust-type-resolution.h
index 0c6413b..2f61a39 100644
--- a/gcc/rust/analysis/rust-type-resolution.h
+++ b/gcc/rust/analysis/rust-type-resolution.h
@@ -1,3 +1,20 @@
+// Copyright (C) 2020 Free Software Foundation, Inc.
+
+// This file is part of GCC.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with GCC; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
 #pragma once
 
 #include "rust-resolution.h"
@@ -38,6 +55,12 @@ public:
     return functionScope.Lookup (ident, fn);
   }
 
+  void PushFunction (AST::Function *fn) { functionStack.push_back (fn); }
+
+  void PopFunction () { functionStack.pop_back (); }
+
+  AST::Function *CurrentFunction () { return functionStack.back (); }
+
   void InsertLocal (std::string ident, AST::LetStmt *let)
   {
     localsPerBlock.Insert (ident, let);
@@ -74,6 +97,8 @@ public:
   }
 
 private:
+  std::vector<AST::Function *> functionStack;
+
   Scope<AST::Function *> functionScope;
   Scope<AST::LetStmt *> localsPerBlock;
   Scope<AST::StructStruct *> structsPerBlock;
diff --git a/gcc/rust/analysis/rust-type-visitor.h b/gcc/rust/analysis/rust-type-visitor.h
new file mode 100644
index 0000000..8cfe156
--- /dev/null
+++ b/gcc/rust/analysis/rust-type-visitor.h
@@ -0,0 +1,261 @@
+// rust-type-visitor.h -- Rust AST Visitor to AST::Type specific
+// Copyright (C) 2020 Free Software Foundation, Inc.
+
+// This file is part of GCC.
+
+// GCC is free software; you can redistribute it and/or modify it under
+// the terms of the GNU General Public License as published by the Free
+// Software Foundation; either version 3, or (at your option) any later
+// version.
+
+// GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+// WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with GCC; see the file COPYING3.  If not see
+// <http://www.gnu.org/licenses/>.
+
+#ifndef RUST_TYPE_VISITOR_H
+#define RUST_TYPE_VISITOR_H
+
+#include "rust-system.h"
+#include "rust-ast-full.h"
+#include "rust-ast-visitor.h"
+#include "rust-scan.h"
+
+namespace Rust {
+namespace Analysis {
+
+class BaseTypeVisitor : public AST::ASTVisitor
+{
+public:
+  // visitor impl
+  // rust-ast.h
+  //  virtual void visit(AttrInput& attr_input);
+  //  virtual void visit(TokenTree& token_tree);
+  //  virtual void visit(MacroMatch& macro_match);
+  virtual void visit (AST::Token &tok) override {}
+  virtual void visit (AST::DelimTokenTree &delim_tok_tree) override {}
+  virtual void visit (AST::AttrInputMetaItemContainer &input) override {}
+  //  virtual void visit(MetaItem& meta_item) override {}
+  //  void vsit(Stmt& stmt) override {}
+  //  virtual void visit(Expr& expr) override {}
+  virtual void visit (AST::IdentifierExpr &ident_expr) override {}
+  //  virtual void visit(Pattern& pattern) override {}
+  //  virtual void visit(Type& type) override {}
+  //  virtual void visit(TypeParamBound& type_param_bound) override {}
+  virtual void visit (AST::Lifetime &lifetime) override {}
+  //  virtual void visit(GenericParam& generic_param) override {}
+  virtual void visit (AST::LifetimeParam &lifetime_param) override {}
+  //  virtual void visit(TraitItem& trait_item) override {}
+  //  virtual void visit(InherentImplItem& inherent_impl_item) override {}
+  //  virtual void visit(TraitImplItem& trait_impl_item) override {}
+  virtual void visit (AST::MacroInvocationSemi &macro) override {}
+
+  // rust-path.h
+  virtual void visit (AST::PathInExpression &path) override {}
+  virtual void visit (AST::TypePathSegment &segment) override {}
+  virtual void visit (AST::TypePathSegmentGeneric &segment) override {}
+  virtual void visit (AST::TypePathSegmentFunction &segment) override {}
+  virtual void visit (AST::TypePath &path) override {}
+  virtual void visit (AST::QualifiedPathInExpression &path) override {}
+  virtual void visit (AST::QualifiedPathInType &path) override {}
+
+  // rust-expr.h
+  virtual void visit (AST::LiteralExpr &expr) override {}
+  virtual void visit (AST::AttrInputLiteral &attr_input) override {}
+  virtual void visit (AST::MetaItemLitExpr &meta_item) override {}
+  virtual void visit (AST::MetaItemPathLit &meta_item) override {}
+  virtual void visit (AST::BorrowExpr &expr) override {}
+  virtual void visit (AST::DereferenceExpr &expr) override {}
+  virtual void visit (AST::ErrorPropagationExpr &expr) override {}
+  virtual void visit (AST::NegationExpr &expr) override {}
+  virtual void visit (AST::ArithmeticOrLogicalExpr &expr) override {}
+  virtual void visit (AST::ComparisonExpr &expr) override {}
+  virtual void visit (AST::LazyBooleanExpr &expr) override {}
+  virtual void visit (AST::TypeCastExpr &expr) override {}
+  virtual void visit (AST::AssignmentExpr &expr) override {}
+  virtual void visit (AST::CompoundAssignmentExpr &expr) override {}
+  virtual void visit (AST::GroupedExpr &expr) override {}
+  //  virtual void visit(ArrayElems& elems) override {}
+  virtual void visit (AST::ArrayElemsValues &elems) override {}
+  virtual void visit (AST::ArrayElemsCopied &elems) override {}
+  virtual void visit (AST::ArrayExpr &expr) override {}
+  virtual void visit (AST::ArrayIndexExpr &expr) override {}
+  virtual void visit (AST::TupleExpr &expr) override {}
+  virtual void visit (AST::TupleIndexExpr &expr) override {}
+  virtual void visit (AST::StructExprStruct &expr) override {}
+  //  virtual void visit(StructExprField& field) override {}
+  virtual void visit (AST::StructExprFieldIdentifier &field) override {}
+  virtual void visit (AST::StructExprFieldIdentifierValue &field) override {}
+  virtual void visit (AST::StructExprFieldIndexValue &field) override {}
+  virtual void visit (AST::StructExprStructFields &expr) override {}
+  virtual void visit (AST::StructExprStructBase &expr) override {}
+  virtual void visit (AST::StructExprTuple &expr) override {}
+  virtual void visit (AST::StructExprUnit &expr) override {}
+  //  virtual void visit(EnumExprField& field) override {}
+  virtual void visit (AST::EnumExprFieldIdentifier &field) override {}
+  virtual void visit (AST::EnumExprFieldIdentifierValue &field) override {}
+  virtual void visit (AST::EnumExprFieldIndexValue &field) override {}
+  virtual void visit (AST::EnumExprStruct &expr) override {}
+  virtual void visit (AST::EnumExprTuple &expr) override {}
+  virtual void visit (AST::EnumExprFieldless &expr) override {}
+  virtual void visit (AST::CallExpr &expr) override {}
+  virtual void visit (AST::MethodCallExpr &expr) override {}
+  virtual void visit (AST::FieldAccessExpr &expr) override {}
+  virtual void visit (AST::ClosureExprInner &expr) override {}
+  virtual void visit (AST::BlockExpr &expr) override {}
+  virtual void visit (AST::ClosureExprInnerTyped &expr) override {}
+  virtual void visit (AST::ContinueExpr &expr) override {}
+  virtual void visit (AST::BreakExpr &expr) override {}
+  virtual void visit (AST::RangeFromToExpr &expr) override {}
+  virtual void visit (AST::RangeFromExpr &expr) override {}
+  virtual void visit (AST::RangeToExpr &expr) override {}
+  virtual void visit (AST::RangeFullExpr &expr) override {}
+  virtual void visit (AST::RangeFromToInclExpr &expr) override {}
+  virtual void visit (AST::RangeToInclExpr &expr) override {}
+  virtual void visit (AST::ReturnExpr &expr) override {}
+  virtual void visit (AST::UnsafeBlockExpr &expr) override {}
+  virtual void visit (AST::LoopExpr &expr) override {}
+  virtual void visit (AST::WhileLoopExpr &expr) override {}
+  virtual void visit (AST::WhileLetLoopExpr &expr) override {}
+  virtual void visit (AST::ForLoopExpr &expr) override {}
+  virtual void visit (AST::IfExpr &expr) override {}
+  virtual void visit (AST::IfExprConseqElse &expr) override {}
+  virtual void visit (AST::IfExprConseqIf &expr) override {}
+  virtual void visit (AST::IfExprConseqIfLet &expr) override {}
+  virtual void visit (AST::IfLetExpr &expr) override {}
+  virtual void visit (AST::IfLetExprConseqElse &expr) override {}
+  virtual void visit (AST::IfLetExprConseqIf &expr) override {}
+  virtual void visit (AST::IfLetExprConseqIfLet &expr) override {}
+  //  virtual void visit(MatchCase& match_case) override {}
+  // virtual void visit (AST::MatchCaseBlockExpr &match_case) override {}
+  // virtual void visit (AST::MatchCaseExpr &match_case) override {}
+  virtual void visit (AST::MatchExpr &expr) override {}
+  virtual void visit (AST::AwaitExpr &expr) override {}
+  virtual void visit (AST::AsyncBlockExpr &expr) override {}
+
+  // rust-item.h
+  virtual void visit (AST::TypeParam &param) override {}
+  //  virtual void visit(WhereClauseItem& item) override {}
+  virtual void visit (AST::LifetimeWhereClauseItem &item) override {}
+  virtual void visit (AST::TypeBoundWhereClauseItem &item) override {}
+  virtual void visit (AST::Method &method) override {}
+  virtual void visit (AST::ModuleBodied &module) override {}
+  virtual void visit (AST::ModuleNoBody &module) override {}
+  virtual void visit (AST::ExternCrate &crate) override {}
+  //  virtual void visit(UseTree& use_tree) override {}
+  virtual void visit (AST::UseTreeGlob &use_tree) override {}
+  virtual void visit (AST::UseTreeList &use_tree) override {}
+  virtual void visit (AST::UseTreeRebind &use_tree) override {}
+  virtual void visit (AST::UseDeclaration &use_decl) override {}
+  virtual void visit (AST::Function &function) override {}
+  virtual void visit (AST::TypeAlias &type_alias) override {}
+  virtual void visit (AST::StructStruct &struct_item) override {}
+  virtual void visit (AST::TupleStruct &tuple_struct) override {}
+  virtual void visit (AST::EnumItem &item) override {}
+  virtual void visit (AST::EnumItemTuple &item) override {}
+  virtual void visit (AST::EnumItemStruct &item) override {}
+  virtual void visit (AST::EnumItemDiscriminant &item) override {}
+  virtual void visit (AST::Enum &enum_item) override {}
+  virtual void visit (AST::Union &union_item) override {}
+  virtual void visit (AST::ConstantItem &const_item) override {}
+  virtual void visit (AST::StaticItem &static_item) override {}
+  virtual void visit (AST::TraitItemFunc &item) override {}
+  virtual void visit (AST::TraitItemMethod &item) override {}
+  virtual void visit (AST::TraitItemConst &item) override {}
+  virtual void visit (AST::TraitItemType &item) override {}
+  virtual void visit (AST::Trait &trait) override {}
+  virtual void visit (AST::InherentImpl &impl) override {}
+  virtual void visit (AST::TraitImpl &impl) override {}
+  //  virtual void visit(ExternalItem& item) override {}
+  virtual void visit (AST::ExternalStaticItem &item) override {}
+  virtual void visit (AST::ExternalFunctionItem &item) override {}
+  virtual void visit (AST::ExternBlock &block) override {}
+
+  // rust-macro.h
+  virtual void visit (AST::MacroMatchFragment &match) override {}
+  virtual void visit (AST::MacroMatchRepetition &match) override {}
+  virtual void visit (AST::MacroMatcher &matcher) override {}
+  virtual void visit (AST::MacroRulesDefinition &rules_def) override {}
+  virtual void visit (AST::MacroInvocation &macro_invoc) override {}
+  virtual void visit (AST::MetaItemPath &meta_item) override {}
+  virtual void visit (AST::MetaItemSeq &meta_item) override {}
+  virtual void visit (AST::MetaWord &meta_item) override {}
+  virtual void visit (AST::MetaNameValueStr &meta_item) override {}
+  virtual void visit (AST::MetaListPaths &meta_item) override {}
+  virtual void visit (AST::MetaListNameValueStr &meta_item) override {}
+
+  // rust-pattern.h
+  virtual void visit (AST::LiteralPattern &pattern) override {}
+  virtual void visit (AST::IdentifierPattern &pattern) override {}
+  virtual void visit (AST::WildcardPattern &pattern) override {}
+  //  virtual void visit(RangePatternBound& bound) override {}
+  virtual void visit (AST::RangePatternBoundLiteral &bound) override {}
+  virtual void visit (AST::RangePatternBoundPath &bound) override {}
+  virtual void visit (AST::RangePatternBoundQualPath &bound) override {}
+  virtual void visit (AST::RangePattern &pattern) override {}
+  virtual void visit (AST::ReferencePattern &pattern) override {}
+  //  virtual void visit(StructPatternField& field) override {}
+  virtual void visit (AST::StructPatternFieldTuplePat &field) override {}
+  virtual void visit (AST::StructPatternFieldIdentPat &field) override {}
+  virtual void visit (AST::StructPatternFieldIdent &field) override {}
+  virtual void visit (AST::StructPattern &pattern) override {}
+  //  virtual void visit(TupleStructItems& tuple_items) override {}
+  virtual void visit (AST::TupleStructItemsNoRange &tuple_items) override {}
+  virtual void visit (AST::TupleStructItemsRange &tuple_items) override {}
+  virtual void visit (AST::TupleStructPattern &pattern) override {}
+  //  virtual void visit(TuplePatternItems& tuple_items) override {}
+  virtual void visit (AST::TuplePatternItemsMultiple &tuple_items) override {}
+  virtual void visit (AST::TuplePatternItemsRanged &tuple_items) override {}
+  virtual void visit (AST::TuplePattern &pattern) override {}
+  virtual void visit (AST::GroupedPattern &pattern) override {}
+  virtual void visit (AST::SlicePattern &pattern) override {}
+
+  // rust-stmt.h
+  virtual void visit (AST::EmptyStmt &stmt) override {}
+  virtual void visit (AST::LetStmt &stmt) override {}
+  virtual void visit (AST::ExprStmtWithoutBlock &stmt) override {}
+  virtual void visit (AST::ExprStmtWithBlock &stmt) override {}
+
+  // rust-type.h
+  virtual void visit (AST::TraitBound &bound) override {}
+  virtual void visit (AST::ImplTraitType &type) override {}
+  virtual void visit (AST::TraitObjectType &type) override {}
+  virtual void visit (AST::ParenthesisedType &type) override {}
+  virtual void visit (AST::ImplTraitTypeOneBound &type) override {}
+  virtual void visit (AST::TraitObjectTypeOneBound &type) override {}
+  virtual void visit (AST::TupleType &type) override {}
+  virtual void visit (AST::NeverType &type) override {}
+  virtual void visit (AST::RawPointerType &type) override {}
+  virtual void visit (AST::ReferenceType &type) override {}
+  virtual void visit (AST::ArrayType &type) override {}
+  virtual void visit (AST::SliceType &type) override {}
+  virtual void visit (AST::InferredType &type) override {}
+  virtual void visit (AST::BareFunctionType &type) override {}
+};
+
+class ArrayTypeVisitor : public BaseTypeVisitor
+{
+public:
+  static AST::ArrayType *Resolve (AST::Type *type)
+  {
+    ArrayTypeVisitor vis;
+    type->accept_vis (vis);
+    return vis.resolved;
+  }
+
+  virtual void visit (AST::ArrayType &type) override { resolved = &type; };
+
+private:
+  ArrayTypeVisitor () : resolved (nullptr) {}
+
+  AST::ArrayType *resolved;
+};
+
+} // namespace Analysis
+} // namespace Rust
+
+#endif // RUST_TYPE_VISITOR_H