On Error - Revision history

Laura: /* Parameters */

2014-09-23T03:24:37Z

Parameters

← Older revision		Revision as of 03:24, 23 September 2014
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	"SYSTEM" displays an error message and causes the system to enter ERROR mode (unless the error is handled elsewhere). See the [[HELP]] error condition for the exception to this rule.		"SYSTEM" displays an error message and causes the system to enter ERROR mode (unless the error is handled elsewhere). See the [[HELP]] error condition for the exception to this rule.

			"GOSUB" transfers control to an error-handling sub-routine (4.2). See [[ON ERROR GOSUB]] for details.

	"IGNORE" causes the system to continue as if the error never happened. It is important to understand that the error-causing statement is terminated (not executed) and normal processing continues with the next statement. This means that if an error occurs while ZDIV IGNORE is used for a WRITE statement, the record would not be written. The one exception to this no-execution rule for IGNORE is with the SOFLOW error condition; in this case the assigned string is truncated to its maximum and the statement is executed.		"IGNORE" causes the system to continue as if the error never happened. It is important to understand that the error-causing statement is terminated (not executed) and normal processing continues with the next statement. This means that if an error occurs while ZDIV IGNORE is used for a WRITE statement, the record would not be written. The one exception to this no-execution rule for IGNORE is with the SOFLOW error condition; in this case the assigned string is truncated to its maximum and the statement is executed.

Laura: /* Syntax */

2014-05-05T15:41:29Z

Syntax

← Older revision		Revision as of 15:41, 5 May 2014
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	===Syntax===		===Syntax===
	ON <error condition> {GOTO< line ref>\|IGNORE\|SYSTEM}		ON <[[error condition]]> {[[GOTO]]< [[line ref]]>\|[[IGNORE]]\|[[SYSTEM]]}

	[[Image:OnError.png\|400px]]		[[Image:OnError.png\|400px]]

Laura: /* Syntax */

2014-04-28T16:16:14Z

Syntax

← Older revision		Revision as of 16:16, 28 April 2014
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	===Syntax===		===Syntax===
	ON <error condition> GOTO< line ref>\|IGNORE\|SYSTEM		ON <error condition> {GOTO< line ref>\|IGNORE\|SYSTEM}

	[[Image:OnError.png\|400px]]		[[Image:OnError.png\|400px]]

Laura: /* Syntax */

2014-04-24T19:05:14Z

Syntax

← Older revision		Revision as of 19:05, 24 April 2014
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	===Syntax===		===Syntax===
			ON <error condition> GOTO< line ref>\|IGNORE\|SYSTEM

	[[Image:OnError.png\|400px]]		[[Image:OnError.png\|400px]]

Laura: /* Syntax */

2013-07-30T21:25:20Z

Syntax

← Older revision		Revision as of 21:25, 30 July 2013
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	*[[HELP]]		*[[HELP]]
	*[[IOERR]]		*[[IOERR]]
	*[[LOCKED]]		*[[Locked Error Cond\|LOCKED]]
	*[[OFLOW]]		*[[OFLOW]]
	*[[PAGEOFLOW]]		*[[PAGEOFLOW]]

Laura: /* Syntax */

2013-06-11T16:00:07Z

Syntax

← Older revision		Revision as of 16:00, 11 June 2013
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	===Syntax===		===Syntax===
	[[Image:OnError.png\|~~300px~~]]		[[Image:OnError.png\|400px]]

	Available Error Conditions:		Available Error Conditions:

Laura: /* Syntax */

2013-06-11T15:59:55Z

Syntax

← Older revision		Revision as of 15:59, 11 June 2013
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	===Syntax===		===Syntax===
	[[Image:OnError.png]]		[[Image:OnError.png\|300px]]

	Available Error Conditions:		Available Error Conditions:

Laura: /* Syntax */

2013-01-23T22:56:53Z

Syntax

← Older revision		Revision as of 22:56, 23 January 2013
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	*[[CONV]]		*[[CONV]]
	*[[ERROR]]		*[[ERROR]]
	*[[FNKEY]] num-expr		*[[FNKey Error Cond\|FNKEY]] num-expr
	*[[HELP]]		*[[HELP]]
	*[[IOERR]]		*[[IOERR]]

Laura: /* Technical Considerations */

2013-01-23T22:11:18Z

Technical Considerations

← Older revision		Revision as of 22:11, 23 January 2013
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	00010 A$=B$		00010 A$=B$

	:5.) Error-handling routines usually end with [[RETRY]] or [[Continue\|CONTINUE]] statements.		:5.) Error-handling routines usually end with [[Retry\|RETRY]] or [[Continue\|CONTINUE]] statements.
	:6.) When ON error statements are used in conjunction with other error-handling techniques, the other techniques take precedence. ON error-cond specifications are used only when the occurring error condition is not otherwise addressed in the error-causing statement or in a referenced Exit statement.		:6.) When ON error statements are used in conjunction with other error-handling techniques, the other techniques take precedence. ON error-cond specifications are used only when the occurring error condition is not otherwise addressed in the error-causing statement or in a referenced Exit statement.
	:7.) When the system is not waiting for operator input, the "FNKEY num-expr" parameter may be used to transfer control to a line when the specified key is pressed. This can be useful for allowing the operator to gracefully interrupt a report.		:7.) When the system is not waiting for operator input, the "FNKEY num-expr" parameter may be used to transfer control to a line when the specified key is pressed. This can be useful for allowing the operator to gracefully interrupt a report.
	:8.) If one of the function keys is pressed during any input operation from the keyboard, no interrupt occurs. Instead, the CMDKEY function is set and pressing <CR> is simulated. This situation is true even when the ATTN, FNKEY or HELP parameters are specified in an ON error~~-cond~~ statement. It is possible to remap function keys (using the KEYBOARD specification in BRConfig.sys) so that pressing them will simulate a <CR> and function key combination. This sequence would cause the INPUT FIELDS to be terminated and FNKEY error processing to occur, even when the function key is pressed during a keyboard input operation.		:8.) If one of the function keys is pressed during any input operation from the keyboard, no interrupt occurs. Instead, the CMDKEY function is set and pressing <Enter> is simulated. This situation is true even when the ATTN, FNKEY or HELP parameters are specified in an ON error condition statement. It is possible to remap function keys (using the KEYBOARD specification in BRConfig.sys) so that pressing them will simulate an <Enter> and function key combination. This sequence would cause the INPUT FIELDS to be terminated and FNKEY error processing to occur, even when the function key is pressed during a keyboard input operation.
	:9.) Even if ON FNKEY IGNORE or ON HELP IGNORE is in effect the pressing of a function key or the <HELP> key causes the CMDKEY function to be set.		:9.) Even if ON FNKEY IGNORE or ON HELP IGNORE is in effect the pressing of a function key or the <HELP> key causes the CMDKEY function to be set.
	:10.) ON error specifications do not apply to immediate statements.		:10.) ON error specifications do not apply to immediate statements.

Laura: /* Technical Considerations */

2013-01-23T22:09:19Z

Technical Considerations

← Older revision		Revision as of 22:09, 23 January 2013
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	00010 A$=B$		00010 A$=B$

	:5.) Error-handling routines usually end with [[RETRY]] or [[CONTINUE]] statements.		:5.) Error-handling routines usually end with [[RETRY]] or [[Continue\|CONTINUE]] statements.
	:6.) When ON error statements are used in conjunction with other error-handling techniques, the other techniques take precedence. ON error-cond specifications are used only when the occurring error condition is not otherwise addressed in the error-causing statement or in a referenced Exit statement.		:6.) When ON error statements are used in conjunction with other error-handling techniques, the other techniques take precedence. ON error-cond specifications are used only when the occurring error condition is not otherwise addressed in the error-causing statement or in a referenced Exit statement.
	:7.) When the system is not waiting for operator input, the "FNKEY num-expr" parameter may be used to transfer control to a line when the specified key is pressed. This can be useful for allowing the operator to gracefully interrupt a report.		:7.) When the system is not waiting for operator input, the "FNKEY num-expr" parameter may be used to transfer control to a line when the specified key is pressed. This can be useful for allowing the operator to gracefully interrupt a report.