-1

I still don't buy the rationale.
If a collection is _That_ small and you _require_ #new: to be faster than #new, use an Array and do things yourself.
Really, there's no need to make #new: complicated.


Best regards
	-Tobias

> On 22.01.2020, at 06:54, commits at source.squeak.org wrote:
> 
> Chris Muller uploaded a new version of Collections to project The Inbox:
> http://source.squeak.org/inbox/Collections-cmm.873.mcz
> 
> ==================== Summary ====================
> 
> Name: Collections-cmm.873
> Author: cmm
> Time: 21 January 2020, 11:54:25.478956 pm
> UUID: 3ec60cd4-3b16-4cf7-98bf-bc85acaa4192
> Ancestors: Collections-ul.871
> 
> Let #new: *always* be a performance-improving choice over #new, when the correct size is known.
> 
> =============== Diff against Collections-ul.871 ===============
> 
> Item was changed:
>  ----- Method: HashedCollection class>>goodPrimeAtLeast: (in category 'sizing') -----
>  goodPrimeAtLeast: lowerLimit
>  	"Answer the smallest good prime >= lowerlimit.
>  	If lowerLimit is larger than the largest known good prime, just make it odd.
>  	Use linear search, and exponential search to speed up cases when lowerLimit is small (<2500 and <100000, respectively).
>  	Assume that there are goodPrimes greater than 100000."
>  	
>  	| highIndex midIndex lowIndex prime |
> - 	lowerLimit <= 7 ifTrue: [
> - 		lowerLimit <= 3 ifTrue: [ ^3 ].
> - 		lowerLimit <= 5 ifTrue: [ ^5 ].
> - 		^7 ].
>  	GoodPrimes ifNil: [ "migration only"
>  		self initializeGoodPrimes ].
>  	lowerLimit < 2500 ifTrue: [
>  		"Use linear search when the limit is small. The boundary is based on measurements."
>  		highIndex := 4. "skip 3 5 and 7"
>  		[ (GoodPrimes at: highIndex) < lowerLimit ] whileTrue: [
>  			highIndex := highIndex + 1 ].
>  		^GoodPrimes at: highIndex ].
>  	lowerLimit < 100000 
>  		ifTrue: [
>  			"Use exponential search when the limit is not too large. The boundary is based on measurements."
>  			highIndex := 1.
>  			[ (GoodPrimes at: highIndex) < lowerLimit ] whileTrue: [
>  				highIndex := highIndex * 2 ].
>  			lowIndex := highIndex // 2 + 1. "highIndex // 2 was smaller than lowerLimit" ]
>  		ifFalse: [
>  			"Regular binary search."
>  			lowIndex := 1.
>  			highIndex := GoodPrimes size.
>  			"Check whether the largest prime would fit"
>  			(GoodPrimes at: highIndex) < lowerLimit ifTrue: [
>  				^lowerLimit bitOr: 1 ]. ].
>  	[ highIndex - lowIndex <= 1 ] whileFalse: [
>  		midIndex := highIndex + lowIndex // 2.
>  		prime := GoodPrimes at: midIndex.
>  		lowerLimit < prime
>  			ifTrue: [ highIndex := midIndex ]
>  			ifFalse: [
>  				lowerLimit > prime
>  					ifTrue: [ lowIndex := midIndex ]
>  					ifFalse: [ ^prime ] ] ].
>  	(GoodPrimes at: lowIndex) >= lowerLimit ifTrue: [ ^GoodPrimes at: lowIndex ].
>  	^GoodPrimes at: highIndex!
> 
> Item was changed:
>  ----- Method: HashedCollection class>>new: (in category 'instance creation') -----
> + new: numberOfElements 
> + 	"Create a Set large enough to hold numberOfElements without growing"
> + 	^ self basicNew initialize:
> + 		(numberOfElements < 3
> + 			ifTrue: [ 3 ]
> + 			ifFalse:
> + 				[ numberOfElements < 4
> + 					ifTrue: [ 5 ]
> + 					ifFalse: [ self sizeFor: numberOfElements ] ])!
> - new: nElements
> - 	"Create a Set large enough to hold nElements without growing"
> - 	^ self basicNew initialize: (self sizeFor: nElements)!
> 
>