cg at cdegroot.com (Cees de Groot) wrote:
	And if you get bored with that, you might want to have some fun and implement
	#, on WriteStream or maybe even on a special class (StringStream?) so you can
	do something like 
	
	  (StringStream , 'foo' , 'bar', 'baz') contents
	
Here it is in WriteStream:

WriteStream>>
    , aCollection
        ^self nextPutAll: aCollection

WriteStream class>>
    , aCollection
	^(self on: (aCollection species new: 16)) , aCollection

Then
    (WriteStream , #(f o o) , #(b a r) , #(u g h)) contents
 => #(f o o b a r u g h)

This is "cute", but not really a good idea.  We _have_ a standard name
for the operation "add all these things to this stream" and it's #nextPutAll:
not #, .  Using #, instead would just be confusing.

Here's a better approach:

    SequenceableCollection>>
    concatenationAs: aClass
	"The receiver should be a sequence of sequences.
	 Return the concatenation of the receiver's element
	 as an instance of aClass, which should be a collection class."
	"#('foo' 'bar' 'ugh') concatenationAs: Array"
	|length result offset delta|

	length := self inject: 0 into: [:sum :each | sum + each size].
	result := aClass new: length.
	offset := 0.
	self do: [:each |
	    delta := each size.
	    result replaceFrom: offset + 1 to: offset + delta
	           with: each startingAt: 1.
	    offset := offset + delta].
	^result
	
    SequenceableCollection>>concatenation
	"The receiver should be a sequence of sequences.
	 Return the concatenation of the receiver's elements
	 as an instance of the first element's species,
	 or as an Array if there is no first element."
	"#((f o o) (b a r) (u g h)) concatenation"

	self isEmpty ifTrue: [^#()].
        ^self concatenationAs: self first species

Then
    {'foo'. 'bar'. 'baz'} concatenation
or in general
    {s1. s2. .... sn} concatenation
will concatenate a bunch of strings with minimal overhead.
#replaceFrom:to:with:startingAt: is a primitive in Array and String,
so not only will the minimal amount of copying be done, but it
will be done about as fast as you _can_ do it in Squeak.