Hi Julien, Interesting, in the last years I've been using a similar set of classes that build groups, and can also nest them, but yours seems more customizable. Thank you for sharing it. I'll give it a try! Esteban A. Maringolo On Mon, Dec 9, 2019 at 11:10 AM Julien Delplanque <julien.delplanque@inria.fr> wrote:
Hello,
I made a small library that reify grouping (that one does via #groupBy: usually): Grouper https://github.com/juliendelplanque/Grouper
It is designed in the same spirit as SortFunction, but for grouping.
Quick example:
The following code snippet using Grouper:
(10 to: 50) groupUsing: [ :integer | integer asString first ]. "an OrderedDictionary( $1->#(10 11 12 13 14 15 16 17 18 19) $2->#(20 21 22 23 24 25 26 27 28 29) $3->#(30 31 32 33 34 35 36 37 38 39) $4->#(40 41 42 43 44 45 46 47 48 49) $5->#(50))"
is equivalent to the following code snippet using built-in #groupedBy: method:
(10 to: 50) groupedBy: [ :integer | integer asString first ] "an OrderedDictionary( $1->#(10 11 12 13 14 15 16 17 18 19) $2->#(20 21 22 23 24 25 26 27 28 29) $3->#(30 31 32 33 34 35 36 37 38 39) $4->#(40 41 42 43 44 45 46 47 48 49) $5->#(50))"
The advantage of using it is that it allows one to compose grouper objects.
Thus, it is easy to describe grouping on 2 or 3 levels.
Fore example:
The power of Grouper is that group description are first-class objects. Thus, it is possible to compose group descriptions in order to group a flat collection on multiple levels.
For example:
groupComposition := [ :integer | integer asString first ] grouper , [ :integer | integer asString second ]. (10 to: 50) groupUsing: groupComposition. "an OrderedDictionary( $1->an OrderedDictionary( $0->#(10) $1->#(11) $2->#(12) $3->#(13) $4->#(14) $5->#(15) $6->#(16) $7->#(17) $8->#(18) $9->#(19)) $2->an OrderedDictionary( $0->#(20) $1->#(21) $2->#(22) $3->#(23) $4->#(24) $5->#(25) $6->#(26) $7->#(27) $8->#(28) $9->#(29)) $3->an OrderedDictionary( $0->#(30) $1->#(31) $2->#(32) $3->#(33) $4->#(34) $5->#(35) $6->#(36) $7->#(37) $8->#(38) $9->#(39)) $4->an OrderedDictionary( $0->#(40) $1->#(41) $2->#(42) $3->#(43) $4->#(44) $5->#(45) $6->#(46) $7->#(47) $8->#(48) $9->#(49)) $5->an OrderedDictionary($0->#(50)))"
On the github, there are more example showing how to build trees with custom objects.
Any feedback for this library is welcome.
I would like to propose it to Pharo in the near future because it would simplify a lot of code in DrTests (related to result tree views, the tree on the right of the UI).
I don't know if it will be possible before next release as we are in feature freeze.
Cheers,
Julien