Re: [PATCHv2] completion: make compatible with zsh

From: Mark Lodato <lodatom@gmail.com>
Date: Aug 31, 2010, 00:55 UTC
Message-ID: <AANLkTimNULQNVZ4hzaNY1ZobPRtj_zj545Xi29guGu4g@mail.gmail.com>
In-Reply-To: <20100830141927.GA16495@neumann>

2010/8/30 SZEDER Gábor <szeder@ira.uka.de>

Show 9 quoted lines

> On Thu, Aug 26, 2010 at 10:45:56PM -0400, Mark Lodato wrote:
> > @@ -2417,3 +2433,29 @@ if [ Cygwin = "$(uname -o 2>/dev/null)" ]; then
> >  complete -o bashdefault -o default -o nospace -F _git git.exe 2>/dev/null \
> >       || complete -o default -o nospace -F _git git.exe
> >  fi
> > +
> > +if [[ -z $ZSH_VERSION ]]; then
>
> -z?  I think you wanted to use -n here, like at the other places.

Oh, yes, sorry.  This was a mistake.  Thanks for catching it.

> Nit: why "if [[ ... ]]"?  FWIW "if [ ... ]" would be enough.

Because you don't need to quote variables with [[ ... ]] --- e.g. [ $lines = 0 ] fails, though in this case this feature does not matter --- and because [[ ... ]] is faster.

Bash 4.1.5:

> time (for (( i = 0; i < 200000; i++ )); do [ -z $foo ]; done)

real 0m3.430s user 0m3.240s sys 0m0.180s

> time (for (( i = 0; i < 200000; i++ )); do [[ -z $foo ]]; done)

real 0m2.219s user 0m2.090s sys 0m0.100s

Zsh 4.3.10:

> time (for (( i = 0; i < 2000000; i++ )); do [ -z $foo ]; done)

(; for ((i = 0; i < 2000000; i++ )) do; [ -z $foo ]; done; ) 13.56s user 1.64s system 99% cpu 15.327 total

> time (for (( i = 0; i < 2000000; i++ )); do [[ -z $foo ]]; done)

(; for ((i = 0; i < 2000000; i++ )) do; [[ -z $foo ]]; done; ) 4.62s user 0.01s system 99% cpu 4.644 total

Is there a reason to prefer [ ... ] ?