struct Node{
};

struct VarNode : public Node{
	public Type *semant( Environ *e )=0;
	public TNode *translate( Environ *e )=0;
	public TNode *evaluate( Environ *e )=0;
};

struct ExprNode : public Node{
	public Type *semant( Environ *e )=0;
	public TNode *translate( Environ *e )=0;
};

struct ExprSeqNode : public Node{
	vector<ExprNode*> exprs;
	public Type *semant( Environ *e );
	public TNode *translate( Environ *e );
	public void push_back( ExprNode *s );
	public int size();
};

struct StmtNode : public Node{
	public void semant( Environ *e )=0;
	public void translate( vector<TNode*> &prog,Environ *e )=0;
};

struct StmtSeqNode : public Node{
	vector<StmtNode*> stmts;
	public void semant( Environ *e );
	public void translate( vector<TNode*> &prog,Environ *e );
	public void push_back( StmtNode *s );
	public int size();
};

struct DeclNode : public Node{
	public void proto( Environ *e )=0;
	public void semant( Environ *e )=0;
	public void translate( vector<TNode*> &prog,Environ *e )=0;
};

struct DeclSeqNode : public Node{
	vector<DeclNode*> decls;
	public void proto( Environ *e );
	public void semant( Environ *e );
	public void translate( vector<TNode*> &prog,Environ *e );
	public void push_back( DeclNode *d );
	public int size();
};

struct BlockNode : public Node{
	DeclSeqNode *decls;
	StmtSeqNode *stmts;
	public void proto( Environ *e );
	public void semant( Environ *e );
	public void translate( vector<TNode*> &prog,Environ *e );
};

struct ProgNode : public Node{
	BlockNode *block;
	public void proto( Environ *e );
	public void semant( Environ *e );
	public void translate( Environ *e,Codegen &codegen );
};