Package: LogBook.m

Version: 1.5 (Oct. 1993)

Author:  Gunther Reiszig

Summary: Log-Book.m is a package for logging of parts of sessions in a
  comfortable way. OpenLog[...] opens and CloseLog[] closes a
  log-book. Between these commands, input, output, and message output
  of the current session are logged. OpenLog[] provides several arguments and 
  options for determining 
    log-book files for In, Out and Msg, resp.
                     (default is set to Mathematica.Log),
	what information is to be logged (Logging -> {In, Out, Msg}),
	what information the headline of the log-book files should contain
	                 (LogLabels, LogLabelUsed),
	what function is to be used to open a log-book (OpeningFunction ->
	                  OpenWrite overwrites),
	how user defined $Pre, $Post, $MessagePrePrint should be used 
					(PrePostOrder -> {-1, 1}),
    what format is used to log the output (FormatType -> Identity).
For examples, see LogBook.Examples.

Keywords:     OpenLog, CloseLog, Log-Book, SessionLog 


LogBook Revision History:
-------------------------
   V. 1.0: Febr. 1993
   V. 1.1, 1.2: Mar - ? 1993:
        *fixed a bug concerning the headline ("opened for...").
        *fixed a bug concerning the order of options
        *fixed a bug concerning opening 2 files with different names
         successfully
        *RuleDelayed in options
        *pripro[..], subset[..]
        *FineDate, RetFail -> local
        *LogLabel: {{___String},{___String}}
        *empty input is not to log
        *Logging -> subset of {In, Out}
        *OpeningFunction->..
        *$Pre, $Post remembers their old values
        *PrePostOrder ->..
        *Pattern for opts changed into opts:Sequence[...
        *Pattern for PrePostOrder changed into {1 | -1, 1 | -1}
   V. 1.3: May, June 1993: Tested with Mma 2.2
        *Comments are logged as inputs (due to the new Mma version 2.2 )
   V. 1.4: Oct. 1993, Tested with Mma 2.2.1
		*Messages may now be logged.
		*RetFail substituted by ThrowFail.
		*ThrowFail and FineDate defined iff !ValueQ[...].
		*Fixed a bug concerning handling of errors: If computation of
		 OpenLog was not sucessful, measures are taken to ensure that
		 sucessfully calling of OpenLog in the same session is not 
		 a-priori impossible.
		*dum, OpenLog::unknown : no longer used.
		*In $Pre, $Post: Values instead of local variables used.
		*func used locally (With[{func...]) instead of 
		 Module[{func...] in OpenLog... :=. 
		*Option LogLabel renamed into LogLabels.
		*Option LogLabelUsed added.
		*Fixed a bug concerning the return value of OpenLog in case
		 instr =!= outstr && MemberQ[ Logging, In] && 
		 MemberQ[ Logging, Out | Msg].
   V. 1.5: Oct. 1993 ...
		*fixed a bug in case Logging->{}
		*fixed a bug concerning taken measures if Log-Book is already
		 open and hence cannot be opened.