Can zsh `else` reserved keyword command be aliased and the lexem itself be repurposed as `fi` keyword command?

[mathieu stumpf guntz <mathieu.stumpf-guntz@epopia.com>]

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Hi everybody,

This is mostly a copy of [a question already posted on 
stackoverflow](https://stackoverflow.com/questions/48006335/can-zsh-else-reserved-keyword-command-be-aliased-and-the-lexem-itself-be-repur). 
Maybe it might have more chance to get an answer over here.

# The problem

Following [ZSH: Call in-built function from zsh function that uses the 
same 
name](https://stackoverflow.com/questions/37498409/zsh-call-in-built-function-from-zsh-function-that-uses-the-same-name) 
and [Run a command that is shadowed by an 
alias](https://unix.stackexchange.com/questions/39291/run-a-command-that-is-shadowed-by-an-alias#39296), 
it might be expected that a command `keyword` equivalent of what 
`builtin` and `command` are doing for their respective eponymous token 
category; so that

     if [ -z 'love' ]; then echo 'sad world'; keyword else echo 
'wonderful world'; fi

would be equivalent to

     if [ -z 'love' ]; then echo 'sad world'; else echo 'wonderful 
world'; fi

This problem was found in the following tricky scenario: being able to 
replace `else` with `alie` and `fi` with `else`. See [Can zsh buildtins 
be 
aliased?](https://stackoverflow.com/questions/47999451/can-zsh-buildtins-be-aliased) 
for more details.

So an hypothetical attempt to implement that, if the `keyword` command 
existed, would be:

   alias alie="keyword else"
   alias else='fi'

# Summary

So, to sum it up, the question is how do you make the following peace of 
zsh code works as expected by the previous command:

     if [ -z 'love' ]; then echo 'sad world'; alie echo 'wonderful 
world'; else

# A first trail

This is not yet a working solution, but here is an idea: using the `-r` 
flag of `enable` and `disable` builtin commands to change visibility of 
the `else` keyword. So:

     alias se='enable -r else; if'
     alias alie='else'
     disable -r else
     alias else="fi; disable -r else"

This unfortunately doesn't work

     se [ -z 'amo' ]; then echo 'trista mondo'; alie echo 'mirinda 
mondo'; else
     # zsh: parse error near `fi'

This is however supposedly on the "else" alias substitution that 
something break, as a non-inline version will indeed enter the 
else-branch and print "mirinda mondo".

Kind regards