The Trunk: Collections-ul.494.mcz

Colin Putney uploaded a new version of Collections to project The Trunk:
http://source.squeak.org/trunk/Collections-ul.494.mcz

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

Name: Collections-ul.494
Author: ul
Time: 25 October 2012, 1:56:50.407 am
UUID: 1b62455b-152d-4ffc-8072-5b6086cb26a8
Ancestors: Collections-cwp.493

- more straightforward String >> #numArgs implementation (early returns, less branches)
- added an optimized version of #canBeToken to ByteSymbol
- removed the sentence about uppercase first letter from String >> #numArgs, because it wasn't true even in 2004

=============== Diff against Collections-fbs.490 ===============

Item was added:
+ ----- Method: ByteString>>canBeToken (in category 'testing') -----
+ canBeToken
+ "Optimized version for the common case."
+
+ ^ (self findSubstring: '~' in: self startingAt: 1 matchTable: Tokenish) = 0
+ !

Item was added:
+ ----- Method: ByteSymbol>>canBeToken (in category 'testing') -----
+ canBeToken
+ "Optimized version for the common case."
+
+ | index |
+ index := 0.
+ [ (index := self findSubstring: '~' in: self startingAt: index + 1 matchTable: Tokenish) = 0 ]
+ whileFalse: [
+ (self at: index) == $_ ifFalse: [ ^false ] ].
+ ^true
+ !

Item was added:
+ ----- Method: String>>canBeToken (in category 'testing') -----
+ canBeToken
+ "Extracted from #numArgs to allow specialization by subclasses"
+
+ ^ self allSatisfy: [:c | c tokenish]!

Item was changed:
  ----- Method: String>>numArgs (in category 'accessing') -----
  numArgs
+ "Answer either the number of arguments that the receiver would take if considered a selector.  Answer -1 if it couldn't be a selector. It is intended mostly for the assistance of spelling correction."
- "Answer either the number of arguments that the receiver would take if considered a selector.  Answer -1 if it couldn't be a selector.  Note that currently this will answer -1 for anything begining with an uppercase letter even though the system will accept such symbols as selectors.  It is intended mostly for the assistance of spelling correction."
 
+ | firstChar numColons start ix |
+ self size = 0 ifTrue: [ ^-1 ].
- | firstChar numColons excess start ix |
- self size = 0 ifTrue: [^ -1].
  firstChar := self at: 1.
+ firstChar isSpecial ifTrue: [
+ 2 to: self size do: [ :i | (self at: i) isSpecial ifFalse: [ ^-1 ] ].
+ ^1 ].
+ firstChar isLetter ifFalse: [ ^-1 ].
+ self canBeToken ifFalse: [ ^-1 ].
+ "Fast colon count"
+ numColons := 0.
+ start := 1.
+ [ (ix := self indexOf: $: startingAt: start) > 0 ] whileTrue: [
+ numColons := numColons + 1.
+ start := ix + 1].
+ (numColons > 0 and: [ self last ~= $: ]) ifTrue: [ ^-1 ].
+ ^numColons!
- (firstChar isLetter or: [firstChar = $:]) ifTrue:
- ["Fast reject if any chars are non-alphanumeric
- NOTE: fast only for Byte things - Broken for Wide"
- Scanner prefAllowUnderscoreSelectors ifFalse:
- [self class isBytes
- ifTrue: [(self findSubstring: '~' in: self startingAt: 1 matchTable: Tokenish) > 0 ifTrue: [^ -1]]
- ifFalse: [2 to: self size do: [:i | (self at: i) tokenish ifFalse: [^ -1]]]].
- "Fast colon count"
- numColons := 0.  start := 1.
- [(ix := self indexOf: $: startingAt: start) > 0]
- whileTrue:
- [numColons := numColons + 1.
- start := ix + 1].
- numColons = 0 ifTrue: [^ 0].
- firstChar = $:
- ifTrue: [excess := 2 "Has an initial keyword, as #:if:then:else:"]
- ifFalse: [excess := 0].
- self last = $:
- ifTrue: [^ numColons - excess]
- ifFalse: [^ numColons - excess - 1 "Has a final keywords as #nextPut::andCR"]].
- firstChar isSpecial ifTrue:
- [self size = 1 ifTrue: [^ 1].
- 2 to: self size do: [:i | (self at: i) isSpecial ifFalse: [^ -1]].
- ^ 1].
- ^ -1.!

Item was added:
+ ----- Method: Symbol>>canBeToken (in category 'testing') -----
+ canBeToken
+ "Since definition of #tokenish depends on a preference, we want to make sure
+ that underscores are always considered tokenish. This is so that selectors created
+ when the preference was turned on don't suddenly become invalid when the
+ preference is turned off."
+
+ ^ self allSatisfy: [:c | c = $_ or: [c tokenish]]!