Thanks guys - I always learn something new from these threads.

> On 17 Mar 2019, at 06:56, Richard O'Keefe <rao...@gmail.com> wrote:
> 
> (1) As it happens, my Smalltalk library *does* have
>     #excludes: and #identityExcludes:
> (2) The definitions are trivial.
>     excludes: item
>       ^(self includes: item) not
>     identityExcludes: item
>       ^(self identityIncludes: item) not
> 
> If you want to execute aBlock when aString is not all zeros
> and ones, just do
>    (aString allSatisfy: [:each | each = $0 or: [each = $1]])
>      ifFalse: [aBlock value].
> or
>    (aString anySatisfy: [:each | each ~= $0 and: [each ~= $1]])
>      ifTrue: [aBlock value].
> or
>    ('01' includesAll: aString) ifFalse: [aBlock value].
> 
> 
> On Sat, 16 Mar 2019 at 11:33, Tim Mackinnon <tim@testit.works> wrote:
> Hi - in my quest to understand the edgier details of Pharo (and Smalltalk) - 
> and driven by fresh thoughts of completing exercism exercises - I was 
> surprised to find that there is no #excludes: operation on collection to 
> mirror the #includes: operation?
> 
> I was curious about this - its seems a strange omission?
> 
> Of course I can inverse it with not, or do things a different way - but we 
> have ifTrue: mirrored with ifFalse, empty/notEmpty so am I missing something?
> 
> I wanted to write something like
> 
> 
> aString detect: [:c | ($0 to: $1) excludes: c] ifFound: aBlock. (Evaluate a 
> block if the string isn’t all 0 and 1’s)
> 
> 
> Of course I can write this as:
> 
> (aString reject: [:c | c = $0 | c = $1)) ifNotEmpty: aBlock
> 
> But as recent messages in this vein have shown me (and taught me lots - 
> thanks to those answering), the answer is often not what I thought.
> 
> Tim
> 
> 

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