NAME

       "LaTeXML::Common::Error" - Error and Progress Reporting and Logging support.

DESCRIPTION

       "LaTeXML::Common::Error" does some simple stack analysis to generate more informative,
       readable, error messages for LaTeXML.  Its routines are used by the error reporting
       methods from LaTeXML::Global, namely "Warn", "Error" and "Fatal".

   Error Reporting
       The Error reporting functions all take a similar set of arguments, the differences are in
       the implied severity of the situation, and in the amount of detail that will be reported.

       The $category is a string naming a broad category of errors, such as "undefined". The set
       is open-ended, but see the manual for a list of recognized categories.  $object is the
       object whose presence or lack caused the problem.

       $where indicates where the problem occurred; passs in the $gullet or $stomach if the
       problem occurred during expansion or digestion; pass in a document node if it occurred
       there.  A string will be used as is; if an undefined value is used, the error handler will
       try to guess.

       The $message should be a somewhat concise, but readable, explanation of the problem, but
       ought to not refer to the document or any "incident specific" information, so as to
       support indexing in build systems.  @details provides additional lines of information that
       may be indident specific.

       "Fatal($category,$object,$where,$message,@details);"
           Signals an fatal error, printing $message along with some context.  In verbose mode a
           stack trace is printed.

       "Error($category,$object,$where,$message,@details);"
           Signals an error, printing $message along with some context.  If in strict mode, this
           is the same as Fatal().  Otherwise, it attempts to continue processing..

       "Warn($category,$object,$where,$message,@details);"
           Prints a warning message along with a short indicator of the input context, unless
           verbosity is quiet.

       "Info($category,$object,$where,$message,@details);"
           Prints an informational message along with a short indicator of the input context,
           unless verbosity is quiet.

       "NoteProgress($message);"
           Prints $message unless the verbosity level below 0.  Typically just a short mark to
           indicate motion, but can be longer; provide your own newlines, if needed.

       "NoteProgressDetailed($message);"
           Like "NoteProgress", but for noiser progress, only prints when verbosity >= 1.

   Internal Functions
       No user serviceable parts inside.  These symbols are not exported.

       "$string = LaTeXML::Common::Error::generateMessage($typ,$msg,$lng,@more);"
           Constructs an error or warning message based on the current stack and the current
           location in the document.  $typ is a short string characterizing the type of message,
           such as "Error".  $msg is the error message itself. If $lng is true, will generate a
           more verbose message; this also uses the VERBOSITY set in the $STATE.  Longer messages
           will show a trace of the objects invoked on the stack, @more are additional strings to
           include in the message.

       "$string = LaTeXML::Common::Error::stacktrace;"
           Return a formatted string showing a trace of the stackframes up until this function
           was invoked.

       "@objects = LaTeXML::Common::Error::objectStack;"
           Return a list of objects invoked on the stack.  This procedure only considers those
           stackframes which involve methods, and the objects are those (unique) objects that the
           method was called on.

AUTHOR

       Bruce Miller <bruce.miller@nist.gov>

COPYRIGHT

       Public domain software, produced as part of work done by the United States Government &
       not subject to copyright in the US.