The libcult trace library provides a general-purpose program tracing facility. The following code fragment can be found in libcult/examples/trace:

struct foo {};

std::ostream&
operator<< (std::ostream& o, foo const&)
{
  return o << "::foo";
}

namespace trace = cult::trace;

trace::stream tout ("main", 4);

int
main ()
{
  using trace::record;

  trace::log::instance ().level (9);

  record a ("main", 2);
  a << "notationally burdensome";
  tout << a;

  record b ("main", 2);
  tout << (b << "a bit better, but still burdensome");

  tout << (record ("main", 2) << "this is"
           << " somewhat"
           << " twisted but nice to be able to");

  tout << "concise, using default level";

  tout << 9 << "concise, using custom level";

  foo f;

  tout << 3 << f << " " << 5;
}

Along with the proper implementation, a null implementation is provided which can be used to completely optimize trace code away. For details see the Inlining code away essay.

Copyright © 2005-2010 Boris Kolpackov.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, version 1.2; with no Invariant Sections, no Front-Cover Texts and no Back-Cover Texts.