dotrain doesn't error on binding collision

[thedavidmeister]

Motivation

I bound some bindings

but they get treated as unbound and so set to 0 values

This 0 binding should only happen for elided/unbound bindings.

Solution

Preserve the binding for bound bindings.

[thedavidmeister]

ok so the issue here is actually when you define the same binding twice there's no error for that

i had one binding bound and one binding elided for the same #raindex-subparser and dotrain didn't complain about the collision