Generate an error condition
error (String_Type msg
The error
function generates a S-lang error condition causing
the interpreter to start unwinding to top-level. It takes a single
string parameter which is displayed on the stderr output device.
The error condition may be cleared via an ERROR_BLOCK
with the
_clear_error
function. Consult A Guide to the S-Lang Language for more
information.
define add_txt_extension (file)
{
if (typeof (file) != String_Type)
error ("add_extension: parameter must be a string");
file += ".txt";
return file;
}
verror, _clear_error, message