Programming Reference:Errors and Warnings - Revision history

Mellinger: /* Assertions */

2011-08-12T14:21:24Z

Assertions

← Older revision		Revision as of 14:21, 12 August 2011
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	Do only use assertions when a failure indicates a programming error, not a user configuration error. Especially, don't use bciassert in the <tt>GenericFilter::Preflight()</tt> function because it will terminate BCI2000, and not allow the user to modify parameter settings. To test for conditions in the <tt>Preflight()</tt> function, use the <tt>PreflightCondition</tt> macro described above.		Do only use assertions when a failure indicates a programming error, not a user configuration error. Especially, don't use bciassert in the <tt>GenericFilter::Preflight()</tt> function because it will terminate BCI2000, and not allow the user to modify parameter settings. To test for conditions in the <tt>Preflight()</tt> function, use the <tt>PreflightCondition</tt> macro described above.

			Unlike the standard <tt>assert</tt> macro, <tt>bciassert</tt> will always be active, not only in debug builds.

	==See also==		==See also==

Mellinger: /* Throwing Exceptions */

2011-08-12T13:34:34Z

Throwing Exceptions

@@ Line 44: / Line 44: @@
   ...
   throw bciexception( "Illegal value of n: " << n );
 ==See also==

Mellinger: /* Throwing Exceptions */

2011-08-12T13:24:26Z

Throwing Exceptions

← Older revision		Revision as of 13:24, 12 August 2011
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	Finally, in case of a non-recoverable error, you may also throw an		Finally, in case of a non-recoverable error, you may also throw an
	exception		exception
	of type <tt>const char*</tt> in order to report an error in the		of type <tt>BCIException</tt> in order to report an error in the
	operator window,		operator window,
	and to terminate the BCI2000 system after the error has been		and to terminate the BCI2000 system after the error has been
	displayed:		displayed.
	throw ~~__FUNC__~~ ": ~~Disk space is exhausted~~";		For convenience, there is a macro <tt>bciexception</tt> that allows you to use stream inserters when specifying the error message:
			#include "BCIException.h"
			...
			throw bciexception( "Illegal value of n: " << n );

	==See also==		==See also==

Mellinger: /* See also */

2007-11-08T17:23:39Z

Mellinger at 10:20, 7 November 2007

2007-11-07T10:20:40Z

← Older revision		Revision as of 10:20, 7 November 2007
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	displayed:		displayed:
	throw __FUNC__ ": Disk space is exhausted";		throw __FUNC__ ": Disk space is exhausted";
	~~-----~~
	==See also:==		==See also==
	[[Programming Reference:Error Handling]] for a more detailed discussion of error reporting facilities.		[[Programming Reference:Error Handling]] for a more detailed discussion of error reporting facilities.

Mellinger at 10:20, 7 November 2007

2007-11-07T10:20:21Z

← Older revision		Revision as of 10:20, 7 November 2007
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	throw __FUNC__ ": Disk space is exhausted";		throw __FUNC__ ": Disk space is exhausted";
	-----		-----
	See also: [[Programming Reference:Error Handling]] for a more detailed discussion of error reporting facilities.		==See also:==
			[[Programming Reference:Error Handling]] for a more detailed discussion of error reporting facilities.

Mellinger at 10:19, 7 November 2007

2007-11-07T10:19:33Z

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	throw __FUNC__ ": Disk space is exhausted";		throw __FUNC__ ": Disk space is exhausted";
	-----		-----
	See also: [[Error Handling]] for a more detailed discussion of error reporting facilities.		See also: [[Programming Reference:Error Handling]] for a more detailed discussion of error reporting facilities.

Atennissen at 19:47, 7 May 2007

2007-05-07T19:47:55Z

← Older revision		Revision as of 19:47, 7 May 2007
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	declared in <tt>shared/BCIError.h</tt>, and while writing output to		declared in <tt>shared/BCIError.h</tt>, and while writing output to
	<tt>bciout</tt> has no side effects, writing to <tt>bcierr</tt> has		<tt>bciout</tt> has no side effects, writing to <tt>bcierr</tt> has
	side		side effects that depend on the system's phase of operation:
	effects that depend on the system's phase of operation:		In preflight phase, the side effect will be a preflight failure, and the system will not start
	In preflight phase, the side effect		unless reconfigured with correct parameters; otherwise, the side effect will
	will be a preflight failure, and the system will ~~refuse to be started~~
	unless
	reconfigured with correct parameters; otherwise, the side effect will
	be system termination after error display.		be system termination after error display.

Mellinger at 19:02, 27 February 2007

2007-02-27T19:02:20Z

← Older revision		Revision as of 19:02, 27 February 2007
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	The names of these output streams are <tt>bciout</tt> and		The names of these output streams are <tt>bciout</tt> and
	<tt>bcierr</tt>,		<tt>bcierr</tt>,
	declared in <tt>shared/~~UBCIError~~.h</tt>, and while writing output to		declared in <tt>shared/BCIError.h</tt>, and while writing output to
	<tt>bciout</tt> has no side effects, writing to <tt>bcierr</tt> has		<tt>bciout</tt> has no side effects, writing to <tt>bcierr</tt> has
	side		side

Mellinger at 17:56, 27 February 2007

2007-02-27T17:56:19Z

New page

==Output Streams==
There are two output channels available to any code inside a BCI2000
module.
Technically, these channels are global objects derived from the STL's
<tt>std::ostream</tt> class. As such, they work much like the global
<tt>std::cout</tt> and <tt>std::cerr</tt> output streams available
inside a
C++ command line program, except that their output will be sent to the
operator
module's log window rather than a terminal window.

==Writing into Error and Warning Streams==
The names of these output streams are <tt>bciout</tt> and
<tt>bcierr</tt>,
declared in <tt>shared/UBCIError.h</tt>, and while writing output to
<tt>bciout</tt> has no side effects, writing to <tt>bcierr</tt> has
side
effects that depend on the system's phase of operation:
In preflight phase, the side effect
will be a preflight failure, and the system will refuse to be started
unless
reconfigured with correct parameters; otherwise, the side effect will
be system termination after error display.

Note that writing into <tt>bcierr</tt> or <tt>bciout</tt> has no effect before the stream's output buffer is flushed by inserting <tt>endl</tt> or <tt>flush</tt>:
bcierr << "Display this immediately!" << endl;

==Convenience Macros==
For the <tt>Preflight</tt> function, there is also a macro
<tt>PreflightCondition</tt> available that is intended to make
checking
for conditions more convenient:
PreflightCondition( Parameter( "MyFirstParam" ) >= 3 );
will result in a message
"A necessary condition is violated: Parameter( "MyFirstParam" ) >= 3"
in the operator window if <tt>MyFirstParam</tt>'s value is below 3.

==Throwing Exceptions==
Finally, in case of a non-recoverable error, you may also throw an
exception
of type <tt>const char*</tt> in order to report an error in the
operator window,
and to terminate the BCI2000 system after the error has been
displayed:
throw __FUNC__ ": Disk space is exhausted";
-----
See also: [[Error Handling]] for a more detailed discussion of error reporting facilities.

← Older revision		Revision as of 17:23, 8 November 2007
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	==See also==		==See also==
	[[Programming Reference:Error Handling]] for a more detailed discussion of error reporting facilities.		[[Programming Reference:Error Handling]] for a more detailed discussion of error reporting facilities.

			[[Category:Framework API]][[Category:Development]]