The Inbox: Collections-ct.877.mcz

Christoph Thiede uploaded a new version of Collections to project The Inbox:
http://source.squeak.org/inbox/Collections-ct.877.mcz

==================== Summary ====================

Name: Collections-ct.877
Author: ct
Time: 17 February 2020, 8:57:49.278239 pm
UUID: bf652ba0-43cc-734d-ac03-7a226cc80463
Ancestors: Collections-ul.875

Extends and realigns version of #findFirst: and #findLast:.

Second, optimized version after many helpful comments by Levente (ul). Thank you!
Replaces Collections-ct.875.

---

Performance analysis:

        #findFirst: - '238 per second. 4.2 milliseconds per run. 0.73956 % GC time.'
        #findFirst:startingAt: - '1,510 per second. 660 microseconds per run. 1.56 % GC time.'
        #findFirst:startingAt:ifNone: - '1,210 per second. 828 microseconds per run. 2.06 % GC time.'
        #findFirst:ifNone: - '214 per second. 4.68 milliseconds per run. 0.65987 % GC time.'
        #findLast: - '210 per second. 4.76 milliseconds per run. 0.66 % GC time.'
        #findLast:startingAt: - '1,380 per second. 724 microseconds per run. 1.72 % GC time.'
        #findLast:startingAt:ifNone: - '1,130 per second. 887 microseconds per run. 2 % GC time.'
        #findLast:ifNone: - '206 per second. 4.86 milliseconds per run. 0.81967 % GC time.'

Comparing to previous version:

        #findFirst: - '193 per second. 5.19 milliseconds per run. 0.5994 % GC time.' (NOW 23.3% faster)
        #findLast: - '213 per second. 4.69 milliseconds per run. 0.71986 % GC time.' (NOW 1.4% slower)
        #findLast:startingAt: - '1,360 per second. 736 microseconds per run. 1.72 % GC time.' (NOW 1.4% faster)

Measurements code:

        random := Random new.
        range := 1 to: 256.
        array := (1 to: 128) collect: [:i | range atRandom: random].
        values := (1 to: 4096) collect: [:i | range atRandom: random].
       
        ({
                #findFirst: -> [
                        values do: [:x |
                                array findFirst: [:y | x = y]]].
                #findFirst:startingAt: -> [
                        values pairsDo: [:x :s |
                                array findFirst: [:y | x = y] startingAt: s]].
                #findFirst:ifNone: -> [
                        values do: [:x |
                                array findFirst: [:y | x = y] ifNone: [123456789 sqrt]]].
                #findFirst:startingAt:ifNone: -> [
                        values pairsDo: [:x :s |
                                array findFirst: [:y | x = y] startingAt: s ifNone: [123456789 sqrt]]].
                #findLast: -> [
                        values do: [:x |
                                array findLast: [:y | x = y]]].
                #findLast:startingAt: -> [
                        values pairsDo: [:x :s |
                                array findLast: [:y | x = y] startingAt: s]].
                #findLast:ifNone: -> [
                        values do: [:x |
                                array findLast: [:y | x = y] ifNone: [123456789 sqrt]]].
                #findLast:startingAt:ifNone: -> [
                        values pairsDo: [:x :s |
                                array findLast: [:y | x = y] startingAt: s ifNone: [123456789 sqrt]]].
        }
                select: [:assoc | array respondsTo: assoc key])
                collect: [:assoc | assoc key -> assoc value bench] as: Dictionary

=============== Diff against Collections-ul.875 ===============

Item was changed:
  ----- Method: SequenceableCollection>>findFirst: (in category 'enumerating') -----
  findFirst: aBlock
  "Return the index of my first element for which aBlock evaluates as true."
 
+ ^ self findFirst: aBlock startingAt: 1!
- | index |
- index := 0.
- [(index := index + 1) <= self size] whileTrue:
- [(aBlock value: (self at: index)) ifTrue: [^index]].
- ^ 0!

Item was added:
+ ----- Method: SequenceableCollection>>findFirst:ifNone: (in category 'enumerating') -----
+ findFirst: aBlock ifNone: anotherBlock
+ "Return the index of my first element for which aBlock evaluates as true. If no element is found, return the value of anotherBlock."
+
+ | index |
+ (index := self findFirst: aBlock) = 0
+ ifTrue: [^ anotherBlock value].
+ ^ index!

Item was added:
+ ----- Method: SequenceableCollection>>findFirst:startingAt: (in category 'enumerating') -----
+ findFirst: aBlock startingAt: minIndex
+ "Return the index of my first element with index >= minIndex for which aBlock evaluates as true."
+
+ minIndex to: self size do: [:index |
+ (aBlock value: (self at: index)) ifTrue: [^index]].
+ ^ 0!

Item was added:
+ ----- Method: SequenceableCollection>>findFirst:startingAt:ifNone: (in category 'enumerating') -----
+ findFirst: aBlock startingAt: minIndex ifNone: anotherBlock
+ "Return the index of my first element with index >= minIndex for which aBlock evaluates as true. If no element is found, return the value of anotherBlock."
+
+ | index |
+ (index := self findFirst: aBlock startingAt: minIndex) = 0
+ ifTrue: [^ anotherBlock value].
+ ^ index!

Item was changed:
  ----- Method: SequenceableCollection>>findLast: (in category 'enumerating') -----
  findLast: aBlock
  "Return the index of my last element for which aBlock evaluates as true."
 
+ ^ self findLast: aBlock startingAt: 1!
- | index |
- index := self size + 1.
- [(index := index - 1) >= 1] whileTrue:
- [(aBlock value: (self at: index)) ifTrue: [^index]].
- ^ 0!

Item was added:
+ ----- Method: SequenceableCollection>>findLast:ifNone: (in category 'enumerating') -----
+ findLast: aBlock ifNone: anotherBlock
+ "Return the index of my last element for which aBlock evaluates as true. If no element is found, return the value of anotherBlock."
+
+ | index |
+ (index := self findLast: aBlock) = 0
+ ifTrue: [^ anotherBlock value].
+ ^ index!

Item was changed:
  ----- Method: SequenceableCollection>>findLast:startingAt: (in category 'enumerating') -----
+ findLast: aBlock startingAt: minIndex
+ "Return the index of my last element with index >= minIndex for which aBlock evaluates as true."
- findLast: aBlock startingAt: i
- "Return the index of my last element with index >= i for which aBlock evaluates as true."
 
+ self size to: minIndex by: -1 do: [:index |
+ (aBlock value: (self at: index)) ifTrue: [^index]].
- | index |
- index := self size + 1.
- [(index := index - 1) >= i] whileTrue:
- [(aBlock value: (self at: index)) ifTrue: [^index]].
  ^ 0!

Item was added:
+ ----- Method: SequenceableCollection>>findLast:startingAt:ifNone: (in category 'enumerating') -----
+ findLast: aBlock startingAt: minIndex ifNone: anotherBlock
+ "Return the index of my last element with index >= minIndex for which aBlock evaluates as true. If no element is found, return the value of anotherBlock."
+
+ | index |
+ (index := self findLast: aBlock startingAt: minIndex) = 0
+ ifTrue: [^ anotherBlock value].
+ ^ index!