Difference between revisions of "ON ERROR"
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==Purpose== | ==Purpose== | ||
Trap program errors | Trap program errors | ||
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==See Also== | ==See Also== | ||
| − | [[ERRNO()]], [[ERROR()]], [[MESSAGE()]], [[ON ESCAPE]], [[ON KEY]], [[RETRY]], [[SET ONERROR]] | + | [[DOSERROR()]], [[DISPLAY CALLS]], [[ERRNO()]], [[ERROR()]], [[LIST CALLS]], [[MESSAGE()]], [[ON ESCAPE]], [[ON KEY]], [[PROCLINE()]], [[PROCNAME()]], [[RETRY]], [[SET ONERROR]], [[STRERROR()]] |
==Description== | ==Description== | ||
| − | The ON ERROR command causes the specified <command> to be executed if an error is encountered in a program. If ON ERROR is specified without a <command>, then the default Recital | + | The ON ERROR command causes the specified <command> to be executed if an error is encountered in a program. If ON ERROR is specified without a <command>, then the default Recital behavior will be restored. By default, Recital will stop execution at the error and an error.mem file will be created |
====<command>==== | ====<command>==== | ||
| − | The <command> can be any Recital | + | The <command> can be any Recital command. After an error is encountered, the ERROR() function will return the error number, and the MESSAGE() function will return the error message. Specifying an '*' as the command causes any errors to be ignored, so should be used with caution. The RETRY command is often used with the ON ERROR trapping facility. |
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<code lang="recital"> | <code lang="recital"> | ||
procedure badfile | procedure badfile | ||
| − | on error | + | on error |
| − | set message to "File does not exist." | + | set message to "File does not exist." |
return to master | return to master | ||
| Line 38: | Line 31: | ||
==Products== | ==Products== | ||
| − | Recital | + | Recital Server, Recital |
[[Category:Documentation]] | [[Category:Documentation]] | ||
[[Category:Commands]] | [[Category:Commands]] | ||
[[Category:Error Handling and Debugging]] | [[Category:Error Handling and Debugging]] | ||
[[Category:Error Handling and Debugging Commands]] | [[Category:Error Handling and Debugging Commands]] | ||
Latest revision as of 10:54, 15 December 2009
Purpose
Trap program errors
Syntax
ON ERROR [<command>]
See Also
DOSERROR(), DISPLAY CALLS, ERRNO(), ERROR(), LIST CALLS, MESSAGE(), ON ESCAPE, ON KEY, PROCLINE(), PROCNAME(), RETRY, SET ONERROR, STRERROR()
Description
The ON ERROR command causes the specified <command> to be executed if an error is encountered in a program. If ON ERROR is specified without a <command>, then the default Recital behavior will be restored. By default, Recital will stop execution at the error and an error.mem file will be created
<command>
The <command> can be any Recital command. After an error is encountered, the ERROR() function will return the error number, and the MESSAGE() function will return the error message. Specifying an '*' as the command causes any errors to be ignored, so should be used with caution. The RETRY command is often used with the ON ERROR trapping facility.
Example
procedure badfile on error set message to "File does not exist." return to master on error do badfile use patrons
Products
Recital Server, Recital
