Re: BUG: $_ empty on null function call

[Micah Waddoups <micah@askmicah.net>]

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Again, please show mercy on me in my innexperience.  The current 
patch-level of the ZSH shell I am using is:
    zsh-5.0.7-0-g208bded
It is the standard "Arch Linux" zsh package as of January 2015.


On 02/09/2015 03:38 AM, Micah Waddoups wrote:
> Hello all,
>   I am still a beginner in developing, or I would tackle this issue 
> directly myself.  The misbehavior is when the command list has a null 
> function with parameters, the last-command-last-parameter ($_) 
> built-in variable goes blank. Example:
>
> |local a=1 b=2 c=3; : One; function { : Two; echo $_; print -l $argv; 
> } $_ Three; print -l $_ Four;
> ## Should print:
> #  Two
> #  One
> #  Three
> #  Three
> #  Four
>
> ## Currently prints:
> #  Two
> #  Three
> #  Four
>
> ## Conversely, when no arguments are given to the null function,
> ## it operates mostly normally, but as if the function were not there:|
> ||local a=1 b=2 c=3; : One; function { : Two; echo $_; print -l $argv; 
> }; print -l $_ Four;|
> ## Outputs:
> #  Two
> #
> #  One
> #  Four
> ##     ( second line is 'print -l' but $argv is empty
> |
>
>   It would seem this unexpected behavior may be the result of an 
> unfinished shell source where the best shell behavior was not clear to 
> the programmer.  I admit dealing with null functions is a minor point 
> of dilema with script writing, but I have gotten super intricate with 
> the beautiful script design and features made available to me by ZSH, 
> and I have found that the behavior suggested at "Should print" above 
> is the only way that is consistent in a large script where an alias 
> may use a null function for better handling of parameters without 
> interfering with any currently same-name functions, or when a Heredoc 
> is used and one wants to grab the last argument to use as the 
> parameter of an immediately following null function.
>
> -- 
> Micah micah@askmicah.net <mailto:micah@askmicah.net>
> AskMicah.Net <http://askmicah.net>, Problem Solving Agency

-- 
Micah micah@askmicah.net <mailto:micah@askmicah.net>
AskMicah.Net <http://askmicah.net>, Problem Solving Agency

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