[NTG-context] Reprocessing part of input

How to do the following eludes me. Inside macro -processing read into a buffer the following part of the input \startmyinput ...\stopmyinput Analogous to input containing \startbuffer[mystoragebuffer] \startmyinput ... \stopmyinput \stopbuffer but now not executed at once, but stored in and executable from a buffer with \getbuffer[mystoragebuffer]. But of course there might be a better way to execute the same code more than once within one run of TeX. Hans van der Meer