9931990b92
Before this commit, the command word was highlighted as "unknown-token" not because alias loops are invalid, as a comment incorrectly claimed, but because the command word «a» resolved to a «b» that was ineligible for being expanded as an alias, and there was no function/builtin/etc. called "b". Add a function "b" to demonstrate that alias loops are valid. I've also filed issue #695 about the overloading of "unknown-token".
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.