Clojure迭代一个向量并向前看/看起来很恐怖

Question

我必须迭代一个矢量,而矢量又将地图作为其项目.我需要比较下一张地图,有时我需要查看我们之前看过的地图.所以有必要展望未来/看后面的功能.我当前的方法是有效的,但我想这是丑陋的,单一的Clojure,我认为必须有更好的(更规范的)方法来实现这一点.

(let [result (apply str (map (fn [{position-before :position compound-before :compund } ; previous term (unfortunately we need to compare all three)
                                        {:keys [word position line tag stem compound grammarpos] :or {grammarpos "0" stem "" } } ; this maps to the current word
                                        {position-ahead :position compound-ahead :compound line-ahead :line}] ; this is for lookahead
                (do some stuff)) ;; now we have position, which is our current position, position-before and position-after to compare with each other
                ;; this is how we map:
                (into  '[{}] (conj grammar '[{}]))
                (next (into  '[{}] (conj grammar '[{}])))
                (next (next (into  '[{}] (conj grammar '[{}]))))))])

至于数据示例的请求,这是向量的一部分:

[{:tag "0", :position "0", :line "0", :stem "dev", :grammarpos "2625", :word "deva"} {:tag "0", :position "0", :line "0", :stem "deva", :grammarpos "4", :word "deva"}]

工作是比较位置,复合等的值,有时向前看,有时看后面.

Answer 1

你可以迭代你的一个partition矢量,大小为3,步长为1.然后,对于矢量中的每个元素,你也可以获得之前和之后你可以用for或者迭代来学习reduce.

一些例子:https://clojuredocs.org/clojure.core/partition