luciano/specter
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

document exact semantics of select*/transform* needed for Navigator

Browse source
This commit is contained in:
Nathan Marz 2016-06-07 14:34:32 -04:00
parent 5087e500b7
commit ec05c14225
1 changed files with 14 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

16
src/clj/com/rpl/specter/protocols.cljx
View file

@ -1,8 +1,20 @@
(ns com.rpl.specter.protocols)
(defprotocol Navigator
(select* [this structure next-fn])
(transform* [this structure next-fn]))
(select* [this structure next-fn]
"An implementation of `select*` must call `next-fn` on each
subvalue of `structure`. The result of `select*` is specified
as follows:
1. `NONE` if `next-fn` never called
2. `NONE` if all calls to `next-fn` return `NONE`
3. Otherwise, any non-`NONE` return value from calling `next-fn`
")
(transform* [this structure next-fn]
"An implementation of `transform*` must use `next-fn` to transform
any subvalues of `structure` and then merge those transformed values
back into `structure`. Everything else in `structure` must be unchanged."
))
(defprotocol Collector
(collect-val [this structure]))