Missing printOn:

[Ducasse]

printOn: aStream

aStream nextPutAll: '('.
(1 to: self numberOfRows) 
	do: [ :r | 
			(self atRow: r) 
				do: [ :each | aStream nextPutAll: each printString ] 
				separatedBy: [ aStream space ]]
	separatedBy: [ aStream cr ].
aStream nextPutAll: ' )'.

but without the printString please!!!

storeOn: aStream
	aStream nextPut: $(; nextPutAll: self class name;
		nextPutAll: ' rows: '; store: numberOfRows;
		nextPutAll: ' columns: '; store: numberOfColumns;
		nextPutAll: ' contents: '; store: contents;
		nextPut: $)