Return true if file is writable

Contract
Return type	boolean
No input parameters.

Water Contract
<method resource.filesystem.file.is_writable _return_type=boolean/>

See also: file, folder, set, get_content, try, if

Returns true if the _subject of type file is not marked as "read-only", otherwise return false .

Example: Standard usage

<file "logical://user/test_file.txt" />.<is_writable />

If we attempt to write to a file that is not writable, an error will result.

<try if_error="error writing to file" >
  <file "logical://user/protected folder/blah_file.txt" />.<set content="new stuff" />
</try>