chickadee » generics » cxr

accesses the tree xs recursively with car and cdr acording to the symbol ads, which must be a combination of a's and d's. So, for example, (cxr 'dada) is equivalent to cdadar. Notice the mnemonics: the x in cxr is replaced by the ads symbol. the first form is a curried version of the second.

Alternatively can be a flat list of pairs consisting of indexes and a's or d's. In this case cdadar is equivalent to (cxr '(1 d 1 a 1 d 1 a)). This is usefull for deep accesses, e.g. (cxr '(1 a 10 d)).