2016 Update

Task/Loop-over-multiple-arrays-simultaneously/AppleScript/loop-over-multiple-arrays-simultaneously.applescript

@@ -0,0 +1,89 @@
+-- zipListsWith :: ([a] -> b) -> [[a]] -> [[b]]
+on zipListsWith(f, xss)
+    set lngLists to length of xss
+
+    -- appliedToNths :: a -> Int -> [b]
+    script appliedToNths
+        on lambda(_, i)
+            -- nthItem :: [a] -> a
+            script nthItem
+                on lambda(xs)
+                    item i of xs
+                end lambda
+            end script
+
+            if i ≤ lngLists then
+                apply(f, (map(nthItem, xss)))
+            else
+                {}
+            end if
+        end lambda
+    end script
+
+    if lngLists > 0 then
+        map(appliedToNths, item 1 of xss)
+    else
+        []
+    end if
+end zipListsWith
+
+
+
+-- TEST
+
+-- Function to apply:
+
+-- concatList [String] -> String
+on concatList(lst)
+    intercalate("", lst)
+end concatList
+
+on run
+    -- Application:
+
+    intercalate(linefeed, ¬
+        zipListsWith(concatList, ¬
+            [["a", "b", "c"], ["A", "B", "C"], [1, 2, 3]]))
+
+end run
+
+
+
+-- GENERIC FUNCTIONS
+
+-- apply (a -> b) -> a -> b
+on apply(f, a)
+    mReturn(f)'s lambda(a)
+end apply
+
+-- intercalate :: Text -> [Text] -> Text
+on intercalate(strText, lstText)
+    set {dlm, my text item delimiters} to {my text item delimiters, strText}
+    set strJoined to lstText as text
+    set my text item delimiters to dlm
+    return strJoined
+end intercalate
+
+-- map :: (a -> b) -> [a] -> [b]
+on map(f, xs)
+    tell mReturn(f)
+        set lng to length of xs
+        set lst to {}
+        repeat with i from 1 to lng
+            set end of lst to lambda(item i of xs, i, xs)
+        end repeat
+        return lst
+    end tell
+end map
+
+-- Lift 2nd class handler function into 1st class script wrapper
+-- mReturn :: Handler -> Script
+on mReturn(f)
+    if class of f is script then
+        f
+    else
+        script
+            property lambda : f
+        end script
+    end if
+end mReturn