Q:

Different kinds of continuations in Racket

Can someone give a relatively simple example of the differences in Racket between call-with-composable-continuation and call-with-current-continuation.
I've worked through the examples in the Racket Guide 10.3 of call-with-composable-continuation, and the examples of call-with-current-continuation in The Scheme Programming language section 3.3  but I'm not clear on the difference.
Could someone give an example where they would give different results in the same context.

A:

A very thorough explanation is found in the paper "Adding Delimited and Composable Control to a Production Programming Environment" by Flatt, Yu, Findler and Felleisen.
http://www.cs.utah.edu/plt/publications/icfp07-fyff.pdf

