invalid subscript error

invalid subscript error

[Sebastian Gniazdowski]

I get following error:

-fast-highlight-process:571: invalid subscript

The line is top here, but unsure if I counted correctly in vim, it
might be the line after || \:
  if [[ -z "${FAST_HIGHLIGHT[cache-path-${__arg}-${_start_pos}]}" || \
     $(( EPOCHSECONDS -
FAST_HIGHLIGHT[cache-path-${__arg}-${_start_pos}-born-at] )) -gt 8 ]];
then

When the error occurs, __arg is:

\\`sub' function, not working {, } highlighting"; prant -r -- "$msg"

Before (z)-split into sequence of $__arg tokens, the line is:

msga==\"-awk.ch: Highlight \\`sub' function, not working {, }
highlighting"; print -r -- "$msg"

_start_pos is just some number

I did quite much but couldn't reproduce on command line. Does anyone
have any clues? I think hash subscript can be anything, and here it
doesn't accept one.

-- 
Best regards,
Sebastian Gniazdowski