public virtual TReturn Visit(DeclarationRefExpression node, TParam param) => throw new NotImplementedException();
public virtual TReturn Visit(DeclarationRefExpression node, TParam param) { return(DefaultReturn); }
public virtual TReturn Visit(DeclarationRefExpression node, TParam param) => throw new NotImplementedException();
public virtual TReturn Visit(DeclarationRefExpression node, TParam param) { return(DefaultReturn); }