Re: Surprising effect of fun() { local FPATH=...; autoload -X }, and a bug

[Bart Schaefer <schaefer@xxxxxxxxxxxxxxxx>]

On Sep 27, 12:07am, Sebastian Gniazdowski wrote:
}
}             eval "function $func {
}                 local FPATH="$PLUGIN_DIR":"${FPATH}"
}                 builtin autoload -X ${opts[*]}
}             }"
} 
} What I astonishingly realized today is that functions autoloaded this
} way can further use autoload builtin purely normally. FPATH visible
} from the specially-autoloaded function is modified, has the required
} added component, and builtin autoload works as expected (even with
} <5.1 Zsh, it has a more specific manual autoload stub).

This will be the case as long as the autoload command AND the first
run of the normally-autoloaded function BOTH happen during the FIRST
run of the "specially-loaded" function.

E.g. suppose we have this silly example:

  --8<-- file "outer" --8<--
    if (( $+functions[inner2] )); then
      inner2
    else
      autoload inner1 inner2
      inner1
    fi
  -->8-- file "outer" -->8--

and we send func=outer through your eval above.  When "outer" is first
run, the call stack will look like

    outer # scope of local FPATH is here
     autoload -X
      outer # "normal autoloads" are here
       inner1 # modified FPATH is still in scope

In this case inner1 will load with the modified FPATH.  On the second
and subsequent runs of "outer", the call stack will look like:

    outer # no FPATH declared
     inner2 # no modified FPATH in scope

thus inner2 will load from the normal fpath.  It's the fpath at time of
function call that matters, not the fpath at time of autoload command.