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It's funny how you can put up with annoyances for years, then one day realize that you can make it much easier. That's what Anthony Lander and I discovered the other day when we were discussing Smalltalk annoyances.

We often need to replace the value in a collection with another value. For example:

   myCollection at: index put: (myCollection at: index) + 1

The corresponding C code for this is:

	myCollection[index]++

Or, as real C programmers would write it: :-)

c[i]++

We can't beat C's brevity, but we can put in a better mechanism that's more general. It's trivial to write a method to allow us to say this:

	myCollection at: index replaceWith: [:value | value + 1]

For dictionaries, we could also do this:

	myCollection at: index replaceWith: [:value | value + 1] ifAbsent: [0]

and:

	myCollection at: index replaceWith: [:value | value + 1] ifAbsentPut: [0]

Now, you can do anything you like in the replaceWith block. It's so nice having an extensible language.