2016 Update

Task/Determine-if-a-string-is-numeric/AppleScript/determine-if-a-string-is-numeric-1.applescript

@@ -0,0 +1,62 @@
+-- isNumString :: String -> Bool
+on isNumString(s)
+    try
+        if class of s is string then
+            set c to class of (s as number)
+            c is real or c is integer
+        else
+            false
+        end if
+    on error
+        false
+    end try
+end isNumString
+
+
+
+-- TEST
+on run
+
+    map(isNumString, {3, 3.0, 3.5, "3.5", "3E8", "-3.5", "30", "three", three, four})
+
+    --> {false, false, false, true, true, true, true, false, false, false}
+
+end run
+
+-- three :: () -> Int
+script three
+    3
+end script
+
+-- four :: () -> Int
+on four()
+    4
+end four
+
+
+-- GENERIC FUNCTIONS FOR TEST
+
+-- 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

Task/Determine-if-a-string-is-numeric/AppleScript/determine-if-a-string-is-numeric-2.applescript

@@ -0,0 +1 @@
+{false, false, false, true, true, true, true, false, false, false}