operator
is
with isnt
will reverse the results.
file string-expression (is | isnt) writable
This operator succeeds if the file named by the string expression exists and is writable by the OmniMark program, or if it does not exist but can be created.
For example, the following code uses the file...is writable
test to make sure that the file is writable:
find-start do when file "myfile.out" is writable open out as file "myfile.out" else put #error "Cannot write to file 'myfile.out'.%n" halt with 1 done