Sharp MZ-800 - 6.8 Error Processing Statements

6.8 Error Processing Statements
ON ERROR GOTO
Format
ON ERROR GOTO Bese number >
<label>
Explanation
Example
Abbreviated Format
ON ERR. G. 2
The ON ERROR GOTO statement causes program execution to branch to <line
number> or <label> if an error occurs. The ERN or ERL system variable can
be used in a trap routine starting at that line to control subsequent processing ac-
cording to the type of error and the line number in which it occurred. Including
a RESUME statement at the end of the error processing routine makes it possible
to return execution to the line at which the error occurred. Executing an ON ER-
ROR GOTO statement cancels the error trap line number defined by the previous
ON ERROR GOTO statement. The error trap line number definition is also can-
celled by executing a CLR statement.
10 ON ERROR GOTO 100
20 INPUT “*X="";X
30 PRINT SQR(X)
40 END
100 PRINT “‘ERROR’’
110 RESUME 20
The program above displays the message “ERROR” and returns to line 20 if an
error occurs.
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