Add valid runnable example for readme

src/zetta/examples/readme.clj

@@ -0,0 +1,79 @@
+(ns zetta.examples.clojure
+  ^{:doc "A parser used on this project's README file"}
+  (:refer-clojure :exclude [char])
+  (:require [clojure.core :as core]
+            [clojure.string :as str]
+            [clojure.java.io :as io]
+            [zetta.core
+             :refer :all]
+            [zetta.combinators
+             :as pc]
+            [zetta.parser.seq
+             :as pseq]
+            [zetta.parser.string
+             :as pstr]))
+
+(defrecord Actor [name movies])
+(defrecord Doctor [name patients])
+(defrecord Programmer [name programs])
+
+(def parse-movie
+  (do-parser
+   pseq/skip-spaces
+   (pstr/take-till #(or (Character/isWhitespace %)
+                        (= % \,)))))
+
+(def parse-patient
+  (do-parser
+   pseq/skip-spaces
+   first-name <- (pstr/take-till #(Character/isWhitespace %))
+   pseq/skip-spaces
+   last-name  <- (pstr/take-till #(or (Character/isWhitespace %)
+                                      (= % \,)))
+   (always [first-name last-name])))
+
+(def parse-person-year
+  (do-parser
+   pseq/skip-spaces
+   year <- pseq/number
+   (if (>= year 1900)
+     (always year)
+     (fail-parser "Expecting year to be greater than 1900"))))
+
+(def parse-program
+  (do-parser
+   pseq/skip-spaces
+   program-year <- parse-person-year
+   pseq/skip-spaces
+   (pseq/char \")
+   program-title <- (pstr/take-till #(= % \"))
+   (pseq/char \")
+   (always [program-year program-title])))
+
+
+(def parse-professional
+  (do-parser
+    pseq/skip-spaces
+    name <- (pstr/take-till #(Character/isSpace %))
+    pseq/skip-spaces
+    profession <- (pstr/take-till #(Character/isSpace %))
+    (always [name profession])
+
+    (cond
+      (= profession "actor")
+      (do-parser
+       movies <- (pc/sep-by1 parse-movie (pseq/char \,))
+       (always (Actor. name movies)))
+
+      (= profession "doctor")
+      (do-parser
+       patients <- (pc/sep-by1 parse-patient (pseq/char \,))
+       (always (Doctor. name patients)))
+
+      (= profession "programmer")
+      (do-parser
+       programs <- (pc/sep-by1 parse-program (pseq/char \,))
+       (always (Programmer. name programs)))
+
+      :else
+      (fail-parser (str "Invalid profession: " profession)))))