ast: Add ConstGenericParam class

This also implements all the necessary boilerplate to allow visitors to
work properly. For now, no operation is performed on const generic
params - similarly to lifetimes

1 files changed, 66 insertions, 0 deletions

diff --git a/gcc/rust/ast/rust-ast.h b/gcc/rust/ast/rust-ast.h
index 2d7d31a..b4d401c 100644
--- a/gcc/rust/ast/rust-ast.h
+++ b/gcc/rust/ast/rust-ast.h
@@ -1342,6 +1342,72 @@ protected:
   }
 };
 
+/**
+ * Representation of const generic parameters
+ */
+class ConstGenericParam : public GenericParam
+{
+  /* Name of the parameter */
+  Identifier name;
+
+  /* Mandatory type of the const parameter - a null pointer is an error */
+  std::unique_ptr<AST::Type> type;
+
+  /**
+   * Default value for the const generic parameter - nullptr indicates a lack
+   * of default value, not an error, as these errors are reported during
+   * parsing.
+   */
+  std::unique_ptr<AST::Expr> default_value;
+
+  Attribute outer_attr;
+  Location locus;
+
+public:
+  ConstGenericParam (Identifier name, std::unique_ptr<AST::Type> type,
+		     std::unique_ptr<AST::Expr> default_value,
+		     Attribute outer_attr, Location locus)
+    : name (name), type (std::move (type)),
+      default_value (std::move (default_value)), outer_attr (outer_attr),
+      locus (locus)
+  {}
+
+  ConstGenericParam (const ConstGenericParam &other)
+    : GenericParam (), name (other.name), type (other.type->clone_type ()),
+      outer_attr (other.outer_attr), locus (other.locus)
+  {
+    if (other.default_value)
+      default_value = other.default_value->clone_expr ();
+  }
+
+  bool has_type () { return type != nullptr; }
+
+  std::unique_ptr<AST::Type> &get_type ()
+  {
+    rust_assert (has_type ());
+
+    return type;
+  }
+
+  std::unique_ptr<AST::Expr> &get_default_value () { return default_value; }
+
+  std::string as_string () const override;
+
+  void accept_vis (ASTVisitor &vis) override;
+
+  Location get_locus () const override final { return locus; }
+
+  Kind get_kind () const override final { return Kind::Const; }
+
+protected:
+  /* Use covariance to implement clone function as returning this object rather
+   * than base */
+  ConstGenericParam *clone_generic_param_impl () const override
+  {
+    return new ConstGenericParam (*this);
+  }
+};
+
 // A macro item AST node - abstract base class
 class MacroItem : public Item
 {