| Copyright | Copyright (C) 2010 Uwe Schmidt |
|---|---|
| License | MIT |
| Maintainer | Uwe Schmidt (uwe@fh-wedel.de) |
| Stability | stable |
| Portability | portable |
| Safe Haskell | None |
| Language | Haskell2010 |
Text.XML.HXT.Arrow.XmlState.ErrorHandling
Description
the basic state arrows for XML processing
A state is needed for global processing options, like encoding options, document base URI, trace levels and error message handling
The state is separated into a user defined state and a system state. The system state contains variables for error message handling, for tracing, for the document base for accessing XML documents with relative references, e.g. DTDs, and a global key value store. This assoc list has strings as keys and lists of XmlTrees as values. It is used to store arbitrary XML and text values, e.g. user defined global options.
The user defined part of the store is in the default case empty, defined as (). It can be extended with an arbitray data type
Synopsis
- changeErrorStatus :: (Int -> Int -> Int) -> IOStateArrow s Int Int
- clearErrStatus :: IOStateArrow s b b
- setErrStatus :: IOStateArrow s Int Int
- getErrStatus :: IOStateArrow s XmlTree Int
- setErrMsgStatus :: IOStateArrow s XmlTree XmlTree
- setErrorMsgHandler :: Bool -> (String -> IO ()) -> IOStateArrow s b b
- sysErrorMsg :: IOStateArrow s XmlTree XmlTree
- errorMsgStderr :: IOStateArrow s b b
- errorMsgCollect :: IOStateArrow s b b
- errorMsgStderrAndCollect :: IOStateArrow s b b
- errorMsgIgnore :: IOStateArrow s b b
- getErrorMessages :: IOStateArrow s b XmlTree
- addToErrorMsgList :: IOStateArrow s XmlTree XmlTree
- filterErrorMsg :: IOStateArrow s XmlTree XmlTree
- issueWarn :: String -> IOStateArrow s b b
- issueErr :: String -> IOStateArrow s b b
- issueFatal :: String -> IOStateArrow s b b
- issueExc :: String -> IOStateArrow s SomeException b
- setDocumentStatus :: Int -> String -> IOStateArrow s XmlTree XmlTree
- setDocumentStatusFromSystemState :: String -> IOStateArrow s XmlTree XmlTree
- documentStatusOk :: ArrowXml a => a XmlTree XmlTree
- errorOutputToStderr :: String -> IO ()
Documentation
changeErrorStatus :: (Int -> Int -> Int) -> IOStateArrow s Int Int Source #
clearErrStatus :: IOStateArrow s b b Source #
reset global error variable
setErrStatus :: IOStateArrow s Int Int Source #
set global error variable
getErrStatus :: IOStateArrow s XmlTree Int Source #
read current global error status
setErrMsgStatus :: IOStateArrow s XmlTree XmlTree Source #
raise the global error status level to that of the input tree
setErrorMsgHandler :: Bool -> (String -> IO ()) -> IOStateArrow s b b Source #
set the error message handler and the flag for collecting the errors
sysErrorMsg :: IOStateArrow s XmlTree XmlTree Source #
error message handler for output to stderr
errorMsgStderr :: IOStateArrow s b b Source #
the default error message handler: error output to stderr
errorMsgCollect :: IOStateArrow s b b Source #
error message handler for collecting errors
errorMsgStderrAndCollect :: IOStateArrow s b b Source #
error message handler for output to stderr and collecting
errorMsgIgnore :: IOStateArrow s b b Source #
error message handler for ignoring errors
getErrorMessages :: IOStateArrow s b XmlTree Source #
if error messages are collected by the error handler for processing these messages by the calling application, this arrow reads the stored messages and clears the error message store
filterErrorMsg :: IOStateArrow s XmlTree XmlTree Source #
filter error messages from input trees and issue errors
issueWarn :: String -> IOStateArrow s b b Source #
generate a warnig message
issueErr :: String -> IOStateArrow s b b Source #
generate an error message
issueFatal :: String -> IOStateArrow s b b Source #
generate a fatal error message, e.g. document not found
issueExc :: String -> IOStateArrow s SomeException b Source #
Default exception handler: issue a fatal error message and fail.
The parameter can be used to specify where the error occured
setDocumentStatus :: Int -> String -> IOStateArrow s XmlTree XmlTree Source #
add the error level and the module where the error occured
to the attributes of a document root node and remove the children when level is greater or equal to c_err.
called by setDocumentStatusFromSystemState when the system state indicates an error
setDocumentStatusFromSystemState :: String -> IOStateArrow s XmlTree XmlTree Source #
check whether the error level attribute in the system state
is set to error, in this case the children of the document root are
removed and the module name where the error occured and the error level are added as attributes with setDocumentStatus
else nothing is changed
documentStatusOk :: ArrowXml a => a XmlTree XmlTree Source #
check whether tree is a document root and the status attribute has a value less than c_err
errorOutputToStderr :: String -> IO () Source #