When :source following code:
----------------------------
function! s:e724()
let a = {}
let a.a = a
return a
endfunction
try
echo s:e724()
catch
echo 'error!'
endtry
echo '---------'
try
12verbose echo s:e724()
catch
echo 'error!'
endtry
----------------------------
https://gist.github.com/2412167
`echo s:e724()` show a result of s:e724() as `{'a': {...}}`. It's abbreviate with ... for referencing recursibly.
But `12verbose echo s:e724()` make be occur error. And throw exception. Them, the code above show error!
It seems that `12verbose` is trying to show detail of the variables, and do self-referencing for the variable. So exception is thrown.
Below is a patch to fix this problem. I checked the part using tv2string().
https://gist.github.com/2412161
Please check and include.