REBOL 3 Concepts: Errors
Errors are exceptions that occur when certain irregular conditions occur.
These conditions range from syntax errors to file or network access errors. Here
are a few examples:
** Syntax error: invalid "date" -- "12-30"
** Near: (line 1) 12-30
1 / 0
** Math error: attempt to divide by zero
** Where: /
** Near: / 0
** Access error: cannot open: %nofile.r reason: -3
** Where: read
** Near: read %nofile.r
Errors are processed within the system as values of the
error! datatype. An error is an object that, if evaluated,
will print an error message and halt. You can also catch errors
and handle them in your script. Errors can be passed to
functions, returned from functions, and assigned to variables.