[BUG] It is possible to create variable which name starts with a digit using g:.{name}

[ZyX]

Consider the following script:

    vim -u NONE -c 'let g:.0="abc"' \
                -c 'let g:0="def"' \
                -c 'echo g:0'
It shows no errors, while expected to show at least one E461 error and one E121 
error. There is no way to make `g:@@@' seem like a valid variable name though.

signature.asc
Description: This is a digitally signed message part.