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From: <psprint@yahoo.com>
To: "zsh-users@zsh.org" <zsh-users@zsh.org>
Subject: Tip of the day: (@)...[(R)...] is equal to (@M)...:#... and faster by 18-21%
Date: Fri, 21 Oct 2016 08:59:56 +0000 (UTC)	[thread overview]
Message-ID: <536851559.167591.1477040396961@mail.yahoo.com> (raw)
In-Reply-To: <536851559.167591.1477040396961.ref@mail.yahoo.com>

Hello,
I've discovered that following code:

found=( "${(@M)history:#(#i)*$~search_pattern*}" )

can be replaced by:

found=( "${(@)history[(R)(#i)*$~search_pattern*]}" )

and the speeds are: 215 ms vs. 175 ms, for "(#i)**" final pattern, ${#history[@]} == 89000, and typeset -U found (resolving to 18500 entries). Performing sequence of searches for word "h", "hi", "his", ..., "history" gives accumulated times 1271 ms vs. 1000 ms, difference is ~ 7*40ms, in check. Measured via zprof, by wrapping block of code with () { ... }.

I wonder if there are there any pitfalls in such replacement?

Best regards,

Sebastian Gniazdowski


       reply	other threads:[~2016-10-21  9:09 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <536851559.167591.1477040396961.ref@mail.yahoo.com>
2016-10-21  8:59 ` psprint [this message]
2016-10-21 16:20   ` Bart Schaefer

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