b52a485c5c
Compute «${#BUFFER}» just once. I haven't measured the effect of this, but
it might just avoid a strlen() every time around the loop, which could add
up for large ${BUFFER}s.
See issue #295.
zsh-syntax-highlighting / highlighters
Navigate into the individual highlighters' documentation to see
what styles ($ZSH_HIGHLIGHT_STYLES keys) each highlighter defines.
Refer to the documentation on highlighters for further information.