This is easier to debug (printing out a lambda doesn't show what values
it checks against) and makes it easier to check that the filter values
are valid.
With the new implementation, each filter is converted to a function,
then all resources are checked if they match any of the filter
functions. This is simpler than the old implementation, where the
resource lookup code was slightly different for some filter forms.
The new syntax supports the same operations as the old syntax, but is
clearer to understand and more extensible in the future. The old syntax
is still supported for now.
The leading underscore is meant to distinguish private (for internal
use only) APIs from public (for external use) APIs. One can argue about
where the line between public and private should be, but if something
is used from other modules (as with read_variable_length_integer) it's
not really private IMHO.
In scripts (like __main__) it also doesn't make much sense to use
leading underscores, because the entire file is never meant to be used
by external code.
For compressed resources, the value of the length attribute can be
accessed much more quickly than the data itself (because it only
requires parsing the header, rather than decompressing the entire
data). This is used to speed up listing of compressed resources on the
command line.
The length_raw attribute is added for symmetry, although it is not
specifically optimized in any case yet.
In most cases the file order is not important and the unsorted output
hurts readability. The performance impact of sorting is relatively
small and barely noticeable even with large resource files.
Previously all non-ASCII characters were hex-escaped on output.
However, many resource files use MacRoman characters in resource names
and sometimes in resource types, so it makes sense to use MacRoman in
the interest of readability.
Previously, when some aspect of a resource's metadata was not present
(e. g. a resource with no name), the description would
explicitly point this out (and e. g. say "unnamed"). Now missing parts
of the metadata are simply omitted from the description, resulting in
cleaner output in many cases.
The resource description formats used by the listings and dumps have
also been unified. Previously the descriptions were structured slightly
differently in each case; this is now no longer the case.
The broken non-seeking read implementation of ResourceFile is removed,
and non-seekable streams are now handled by reading the entire stream
data first and wrapping it in a BytesIO to make it seekable.
The manual selection of seeking/non-seeking reading has been removed as
well, since it is no longer needed and was already nearly useless.
