Re: [Boost-users] Boost::Tokenizer / "string iterators incompatible" error on Visual C++ 2010 Express - runs ok on gcc4.6.0

Subject: Re: [Boost-users] Boost::Tokenizer / "string iterators incompatible" error on Visual C++ 2010 Express - runs ok on gcc4.6.0
From: Nathan Crookston (nathan.crookston_at_[hidden])
Date: 2011-08-01 14:26:55

Hi Asif,

On Mon, Aug 1, 2011 at 10:45 AM, asif saeed <asif.lse2_at_[hidden]> wrote:
> Base(std::string s) : sep_(";"),
> tok_(s,sep_),
> i_(tok_.begin())
> {
> }

These lines are your problem -- the tokenizer stores the iterators
from the string 's', but once the constructor is exited (prior to the
body of the derived class being called) the argument 's' is destroyed
-- invalidating the iterators stored by the tokenizer data member.

Try the following change to Base:

class Base
{
public:
  typedef boost::char_separator<char> sep_type_t;
  typedef boost::tokenizer<sep_type_t> tokenizer_t;

  Base(std::string s)
    : s_(s),
      sep_(";"),
      tok_(s_,sep_),
      i_(tok_.begin())
  {}

  std::string nextToken()
  {
    if (i_!=tok_.end())
      return *i_++;
    else
      return "";
  }

protected:
  std::string s_;
  sep_type_t sep_;
  tokenizer_t tok_;
  tokenizer_t::iterator i_;
};

HTH,
Nate