LaTeXML::Common::Error3pm
Error and progress reporting and logging support.
Overview
"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".
The general idea is that a minimal amount should be printed to STDERR (possibly with colors, spinners, etc if it is a terminal), and more complete information is printed to a log file. Neither of these are enabled, by default; see below.
- "SetVerbosity($verbosity);"
-
Controls the verbosity of output to the terminal; default is 0, higher gives more information, lower gives less. A verbosity less than 0 inhibits all output to STDERR.
- "UseSTDERR(); ... UseSTDERR(undef);"
-
"UseSTDERR();"Enables and initializes STDERR to accept messages. If this is not called, there will be no output to STDERR."UseSTDERR(undef);"disables STDERR from further messages.
- "UseLog($path, $append); ... UseLog(undef);"
-
"UseLog($path, $append);"opens a log file on the given path. If$appendis true, this file will be appended to, otherwise, it will be created initially empty. If this is not called, there will be no log file."UseLog(undef);"disables and closes the log file.
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
$messagealong with some context. In verbose mode a stack trace is printed.
- "Error($category,$object,$where,$message,@details);"
-
Signals an error, printing
$messagealong with some context. If in strict mode, this is the same asFatal(). Otherwise, it attempts to continue processing..
- "Warn($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,$message,@details);"
-
Prints an informational message along with a short indicator of the input context, unless verbosity is quiet.
Progress Reporting
- "Note($message);"
-
General status message, printed whenever verbosity at or above 0, to both STDERR and the Log file (when enabled).
- "NoteLog($message);"
-
Prints a status message to the Log file (when enabled).
- "NoteSTDERR($message);"
-
Prints a status message to the terminal (STDERR) (when enabled).
- "ProgressSpinup($stage);"
-
Begin a processing stage, which will be ended with
ProgressSpindown($stage); This prints a message to the log such as "(stage... runtime)", where runtime is the time required. In conjunction withProgressStep(), creates a progress spinner on STDERR.
- "ProgressSpinup($stage);"
-
End a processing stage bugin with
"ProgressSpindown($stage);".
- "ProgressStep();"
-
Steps a progress spinner on STDERR.
Debugging
Debugging statements may be embedded throughout the program. These are associated with a feature keyword. A given feature is enabled using the command-line option "--debug=feature".
- "Debug($message) if $LaTeXML::DEBUG{$feature}"
-
Prints
$messageif debugging has been enabled for the given feature.
- "DebuggableFeature($feature,$description)"
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Declare that
$featureis a known debuggable feature, and give a description of it.
- CheckDebuggable()
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A untility to check and report if all requested debugging features actually have debugging messages declared.
Internal Functions
No user serviceable parts inside. These symbols are not exported.
- "$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.
$typis a short string characterizing the type of message, such as "Error".$msgis the error message itself. If$lngis true, will generate a more verbose message; this also uses the VERBOSITY set in the$STATE. Longer messages will show a trace of the objects invoked on the stack,@moreare 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.
Releases
6 releases since Debian 8 (Jessie); the text changed 5 times.