From: Alexander Nasonov (alnsn_at_[hidden])
Date: 2004-11-14 11:51:13
Markus Sch?pflin wrote:
> I have been using some helper macros for tracing which use the boost PP
> library.
>
> Basically it looks liket this:
>
> int X::foo(char* buf, size_t len)
> {
> some_log_object << STREAM_VARS_SEQ((buf)(len));
> }
This is fine except that it doesn't look like a valid function call.
IMO, function call style is easier to remember.
> This expands to
>
> "buf=" << buf << ",len=" << len
>
> What I like most is that you can specify expressions during tracing like
> this: STREAM_VARS_SEQ((buf[0])(2*len)) which of course gets you
>
> "buf[0]=" << buf[0] << ",2*len" << 2*len
>
> While usage is not really restricted to tracing, that where it gets used
> currently.
This is nice for general things but not that nice for call traces.
They are special case of logging with some specific requirements.
Some of them might be:
- strace/ltrace format
- function decls
- Object identities (== dynamic_cast<void*>(this) for poly classes)
primarily for sequence diagrams
Uniform interface could let you switch between different formats without
rewriting any tracing code.
-- Alexander Nasonov