Yeah I've not studied that interpreter so if that's your specific interest no luck sadly; rank is an easy idea but wouldn't surprise me if there's some trick to it in an implementation that short.
I think it'd be easier to untangle if you already had a working knowledge of the language but given the line-noisy look of J I can't blame you for trying the shortcut.
The interactive J labs are very good. You might also find the J for C programmers discussion of rank particularly helpful if you are looking at learning by understanding an implementation.
I figure the array languages will make a minor comeback soon what with gpus / larrabee / etc showing up on the horizon and what with more-versatile input devices showing up (making it easier to go back to funky symbols instead of line noise).
I think it'd be easier to untangle if you already had a working knowledge of the language but given the line-noisy look of J I can't blame you for trying the shortcut.
The interactive J labs are very good. You might also find the J for C programmers discussion of rank particularly helpful if you are looking at learning by understanding an implementation.
I figure the array languages will make a minor comeback soon what with gpus / larrabee / etc showing up on the horizon and what with more-versatile input devices showing up (making it easier to go back to funky symbols instead of line noise).