Hello, I have solved the hamming challenge of exercism where I have to find in how many places two strings are different. my solution is : distanceStrand1: aString strand2: aString2    aString size == aString2 size       ifFalse: [ DomainError signal: (self messageFor: aString strand2: aString2) ].    ^ (1 to: aString size)       sumNumbers: [ :index |          (aString at: index) == (aString2 at: index)             ifTrue: [ 0 ]             ifFalse: [ 1 ] ] messageFor: aString strand2: aString2    aString notEmpty & aString2 notEmpty       ifTrue: [ ^ 'left and right strands must be of equal length' ].    aString ifEmpty: [ ^ 'left strand must not be empty' ].    ^ 'right strand must not be empty' Can this be improved? Roelof