second commit

src/clj/transducerpres/slides/how.clj

@@ -0,0 +1,70 @@
+(ns transducerpres.slides.how
+    (:require [transducerpres.slides.util :refer [defslide defmarkdownslide
+                                                  clj-code markdown-slide
+                                                  markdown-part]]))
+
+(defslide intro-slide
+    [:h3 "How do we create transducers?"]
+    [:h3 "How do we use transducers?"])
+
+(defn- func-link-bullet [name]
+    (str "* `" name "`"))
+
+(def transducer-functions (clojure.string/split "map cat mapcat filter remove take take-while take-nth drop drop-while replace partition-by partition-all keep keep-indexed map-indexed distinct interpose dedupe random-sample" #" "))
+
+(defn transducer-function-list []
+    (clojure.string/join "\n" (map func-link-bullet transducer-functions)))
+
+(defmarkdownslide how-to-create
+    "#### How to create transducers?"
+    ""
+    "The majority of data processing method implement an arity that returns"
+    "a transducer.  The following functions produce a transducer when the "
+    "input collection is omitted:"
+    ""
+    (transducer-function-list))
+
+(defmarkdownslide how-to-use
+    "#### How to use a transducer?"
+    ""
+    "* **transduce** is can be use like reduce"
+    "* **eduction** is used to create reducible/iterable"
+    "* **into** is used to append data to an existing collection"
+    "* **sequence** can create a sequence from transducer")
+
+(defslide example-1
+    (markdown-part
+        "#### example 1")
+    (clj-code
+        "(def xform (map #(* 2 %)))"
+        ""
+        "(transduce xform + 0 (range 10))"
+        ";; 90"
+        ""
+        "(eduction xform (range 10))"
+        ";; (0 2 4 6 8 10 12 14 16 18) ; an eduction"
+        ""))
+
+
+(defslide example-2
+    (markdown-part
+        "#### example 1... part 2")
+    (clj-code
+        "(def xform (map #(* 2 %)))"
+        ""
+        "(into [1 2] xform (range 10))"
+        ";; [1 2 0 2 4 6 8 10 12 14 16 18]"
+        ""
+        "(into (list 1 2) xform (range 10))"
+        ";; (18 16 14 12 10 8 6 4 2 0 1 2)"
+        ""
+        "(sequence xform (range 10))"
+        ";; (0 2 4 6 8 10 12 14 16 18) ; lazy sec"))
+
+
+(defslide how-to-create-slides
+    intro-slide
+    how-to-create
+    how-to-use
+    example-1
+    example-2)