ERROR
=====

Function
--------

**ERROR** simulates a Basic error with the advantage that it allows user
defined codes. For a list of Basic error messages, see 
:doc:`../basic-programming/errors-and-warnings`.

Syntax
------

ERROR n

where 0<n<255

Example
-------

::

   10 INPUT a,b
   20 ON ERROR GOT0 100
   30 IF a>b THEN ERROR 156
   40 GOTO 10
   100 IF ERR = 156 THEN PRINT "a>b error"
   110 RESUME 10

Remarks
-------

The ERROR statement neatly traps errors and forces the printing of a
Basic error message. If the error number is undefined in Basic, then
processing can be forced to restart at another line to print a user
defined message. When ERROR is set to n, this number may be recovered
with :doc:`ERR <err-erl>`, and the line number with
:doc:`ERL <err-erl>`.

After a forced user error trap, a suitable :doc:`resume`
command must be executed to ensure correct program operation.