Add Python 3 support

[sscherfke]

The homebrewed MacVim can only be installed with either Python 2 *or 3 support, but not both. So I enabled Python 3 support and noticed that splice.vim does not work with Python 3.

I think it is “relatively” easy to support both versions. The Python code looks relatively compatible with both versions. Maybe you have to fix the relative-import thing introduced with Python 3.3(?). You also need to modify autoload/splice.vim as followed (inspired by the python-mode plug-in which supports both Python versions). You basically define aliases for pyfile and python depending on the Python version and use them instead of the orginal commands:

" [...]

" Python version check {{{

if has('python')
    let s:has_supported_python = 2
python << ENDPYTHON
import sys, vim
if sys.version_info[:2] < (2, 5):
    vim.command('let s:has_supported_python = 0')
ENDPYTHON
    " Define aliases to pyfile and python
    let s:splice_pyfile = 'pyfile'
    command! -nargs=1 SplicePython python <args>
elseif has('python3')
    let s:has_supported_python = 3
    " Define aliases to py3file and python3
    let s:splice_pyfile = 'py3file'
    command! -nargs=1 SplicePython python3 <args>
else
    let s:has_supported_python = 0
endif
" [...]

" Wrappers {{{

function! splice#SpliceInit() "{{{
    let python_module = fnameescape(globpath(&runtimepath, 'autoload/splice.py'))
    exe s:splice_pyfile . ' ' . python_module
    SplicePython SpliceInit()
endfunction "}}}

" [...]

" }}}

Please let me now if I can help you (e.g., with testing).

Splice.vim is awesome. Thanks! :-)

[sscherfke]

I created a pull request over at bitbucket.