instaparse example (CSV parser)

example.instaparse.clj

(ns example.instaparse
  (:require [instaparse.core :refer [parser transform]]
            [hiccup.core :refer [html]]))

(def csv-bnf "https://gist.github.com/mnzk/5426024/raw/11de5851adc5b3dd704ec4079c22aa6ff8d131df/csv-bnf-rfc4180.txt")
(def csv-parser (parser csv-bnf))

(def data-file "/path/to/data.csv")
(def tree (csv-parser (slurp data-file)))

(def csv-hiccup-transform
  (let [take-even #(take-nth 2 %)]
    (partial transform
             {:file #(->> (take-even %&) (cons :table) vec)
              :header #(->> (take-even %&) (cons :tr) vec)
              :record #(->> (take-even %&) (cons :tr) vec)
              :name #(vector :th %)
              :field #(vector :td %)
              :escaped #(->> (rest %&) drop-last (apply str))
              :2DQUOTE (constantly "\"")
              :non-escaped str
              :CRLF str
              :CR (constantly "[CR]")
              :LF (constantly "[LF]")
              :COMMA identity
              :TEXTDATA identity})))

(print (html (csv-hiccup-transform tree)))
;;=> <table><tr><td>aa</td><td>bb</td></tr><tr><td>cc</td><td>dd,ee"F"</td></tr><tr><td></td><td>gg[CR][LF]hh</td></tr></table>