[boost] RFC: Extending boost::escaped_list_separator<> with an empty_token_policy.

From: Eddy L O Jansson (eddy_at_[hidden])
Date: 2004-10-05 22:08:57

  Boost / Tokenizer / Escaped List Separator - empty_token_policy patch

  What?

   This url[0]/archive[1] contains a trivial patch to Boost 1.31.0 which
   extends the default escaped_list_separator<> tokenizer function with an
   optional empty_token_policy. In addition, a patch to update the
   documentation to reflect this change as well as a new example
   program demonstrating its use, is included also.

   The patch implements the safe default of boost::keep_empty_tokens
   such that a patched version of this library behaves exactly as the
   old one, unless specifically instructed not to. This is done by
   setting empty_tokens to boost::drop_empty_tokens in the constructor.

  Why?

   This gives you the usual benefits of "Escaped List Separator" -- the ability
   to specify and use escape and quote characters -- but without the downside
   of always having to deal with empty tokens by hand. This simplifies client
   code.

   The "empty tokens" policy is already available in the less sexy
   char_separator<> implementation, I simply brought it forward to
   escaped_list_separator<> too.

  Why not?

   It might be redundant.
   I might have fubared the implementation.

  Where?

[0] http://klopper.net/~eddy/src/boost-tokenizer/
[1] http://gazonk.org/~eloj/files/temp/eloj-boost-tokenizer-policy-patch.rar

-- 
"IBM clearly did contribute a lot of the Unix-related information into Linux.
  We just don't know what it is." -- Kevin McBride, legal mastermind.
Eddy L O Jansson     |     http://gazonk.org/~eloj