Note: no need for #collect:thenFold: family, one can implement min as
min
^ self detectMin: [ :x | x ]
if you want to reuse existing one.
But actually, the issue is, min: and max: are not there (correctly) for
strings.
Herby
Richard O'Keefe wrote:
#('a' 'b' 'c') min
also fails on the grounds that ByteStrings don't understand #min:.
What's worse is that ByteString and ByteSymbol *do* have #max:,
but it's something quite different (and arguably broken).
max: aBlock
| max |
self ifEmpty: [ ^ nil ].
max := aBlock value: self first.
self
allButFirstDo:
[ :each |
| value |
value := aBlock value: each.
max := max max: value ].
^ max
It would be better if the TComparable #min: and #max:
were available and the current #max: renamed to something else.
I have this in an extension to GNU Smalltalk:
Collection extend [
collect: collectBlock thenFold: foldBlock [
|started result|
started := result := nil.
self do: [:each | |v|
v := collectBlock value: each.
result := started ifNil: [started := self. v]
ifNotNil: [foldBlock value: result value: v]].
^started ifNil: [SystemExceptions.EmptyCollection signalOn: self]
ifNotNil: [result]
]
collectThenMin: collectBlock [
^self collect: collectBlock thenFold: [:acc :y | acc min: y]
]
min [
^self collectThenMin: [:each | each]
]
collectThenMax: collectBlock [
^self collect: collectBlock thenFold: [:acc :y | acc max: y]
]
max [
^self collectThenMax: [:each | each]
]
]
CharacterArray extend [
max: other [
^self < other ifTrue: [other] ifFalse: [self]
]
min: other [
^self < other ifTrue: [self] ifFalse: [other]
]
]
