//===--- ASTNode.cpp - Swift Language ASTs --------------------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2016 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See http://swift.org/LICENSE.txt for license information
// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
//
// This file implements the ASTNode, which is a union of Stmt, Expr, and Decl.
//
//===----------------------------------------------------------------------===//

#include "swift/AST/ASTNode.h"
#include "swift/AST/Decl.h"
#include "swift/AST/Expr.h"
#include "swift/AST/Stmt.h"
#include "swift/Basic/SourceLoc.h"

using namespace swift;

SourceRange ASTNode::getSourceRange() const {
  if (const Expr *E = this->dyn_cast<Expr*>())
    return E->getSourceRange();
  if (const Stmt *S = this->dyn_cast<Stmt*>())
    return S->getSourceRange();
  if (const Decl *D = this->dyn_cast<Decl*>())
    return D->getSourceRange();
  llvm_unreachable("unsupported AST node");
}

/// \brief Return the location of the start of the statement.
SourceLoc ASTNode::getStartLoc() const {
  return getSourceRange().Start;
}

/// \brief Return the location of the end of the statement.
SourceLoc ASTNode::getEndLoc() const {
  return getSourceRange().End;
}

void ASTNode::walk(ASTWalker &Walker) {
  if (Expr *E = this->dyn_cast<Expr*>())
    E->walk(Walker);
  else if (Stmt *S = this->dyn_cast<Stmt*>())
    S->walk(Walker);
  else if (Decl *D = this->dyn_cast<Decl*>())
    D->walk(Walker);
  else
    llvm_unreachable("unsupported AST node");
}