On Thu, May 3, 2018 at 10:12 AM, Chris Muller <asqueaker at gmail.com> wrote:

> +1.  Not only that, why the call to #basicSize and #basicAt:.  Really?
>
> It's like...  not even Smalltalk anymore...   :(
>

What?  This is a workhorse method, and you want to create a block, and
apply the block to each element, and convert each element from a character
to an integer, when basicAt: yields (and has always yielded) integers in
strings?  You think that one line with a block and a high-level iterator is
so much better than a two line with a simpler inner loop?

| strings nothing allSatisfy basicAt |
strings := String allSubInstances.
strings := strings, strings, strings, strings, strings.
nothing := [:s|].
allSatisfy := [:s| s isAsciiStringWithAllSatisfy].
basicAt := [:s| s isAsciiStringWithBasicAt].
Smalltalk garbageCollect.
1 to: 2 do:
[:ign| times := { nothing. allSatisfy. basicAt } collect: [:block| [strings
do: block] timeToRun]].
(times second - times first / (times third - times first) asFloat) roundTo:
0.1

Answers range from 5.1 to 5.7 on 64-bits Mac OS X.

You really want that elegance for something that is 5 times slower but one
line shorter?  I did this because I saw Patrick inline isAsciiString in
mail message processing, and I thought a) his method would read better if
it used isAsciiString, and b) isAsciiString can be implemented much better
without affecting clients, so I went ahead.  Part of the beauty of
Smalltalk is that clients are insulated from implementation so that
implementations can be improved.  Since when has that not been a part of
Smalltalk?


> On Thu, May 3, 2018 at 3:41 AM, Tobias Pape <Das.Linux at gmx.de> wrote:
> > Hi Eliot
> >
> >> On 03.05.2018, at 09:56, commits at source.squeak.org wrote:
> >>
> >> Eliot Miranda uploaded a new version of Collections to project The
> Trunk:
> >> http://source.squeak.org/trunk/Collections-eem.792.mcz
> >>
> >> ==================== Summary ====================
> >>
> >> Name: Collections-eem.792
> >> Author: eem
> >> Time: 3 May 2018, 12:55:52.175146 am
> >> UUID: 7d8995ed-835e-44b0-bf4c-0b0780f5c96f
> >> Ancestors: Collections-pre.791
> >>
> >> Four times faster implementation of isAsciiString.
> >>
> >> =============== Diff against Collections-pre.791 ===============
> >>
> >> Item was changed:
> >>  ----- Method: String>>isAsciiString (in category 'testing') -----
> >>  isAsciiString
> >> +     "Answer if the receiver contains only ascii characters.
> >> +      Inline ^self allSatisfy: [ :each | each asciiValue <= 127 ] for
> speed."
> >> +     1 to: self basicSize do: [:i| (self basicAt: i) > 127 ifTrue:
> [^false]].
> >> +     ^true!
> >> -
> >> -     ^self allSatisfy: [ :each | each asciiValue <= 127 ]!
> >>
> >>
> >
> > Although I am in awe of the performance improvement, I am curious wether
> it really pays of to inline #allSatify: here, in terms of performance vs.
> readability.
> >
> > I presume that, given the current use of #isAsciiString, we can stay
> with the more compact, readable version that does not need the 'caveat
> lector'-comment at the beginning of the method.
> >
> >
> > Best regards
> >         -Tobias
> >
> >
>
>


-- 
_,,,^..^,,,_
best, Eliot
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