Initial data commit

Task/Determine-if-a-string-is-numeric/REBOL/determine-if-a-string-is-numeric.rebol

@@ -0,0 +1,33 @@
+REBOL [
+	Title: "Is Numeric?"
+	URL: http://rosettacode.org/wiki/IsNumeric
+]
+
+; Built-in.
+
+numeric?: func [x][not error? try [to-decimal x]]
+
+; Parse dialect for numbers.
+
+sign:   [0 1 "-"]
+digit:  charset "0123456789"
+int:    [some digit]
+float:  [int "." int]
+number: [
+	sign float ["e" | "E"] sign int |
+	sign int ["e" | "E"] sign int |
+	sign float |
+	sign int
+]
+
+pnumeric?: func [x][parse x number]
+
+; Test cases.
+
+cases: parse {
+   10 -99
+   10.43 -12.04
+   1e99 1.0e10 -10e3 -9.12e7 2e-4 -3.4E-5
+   3phase  Garkenhammer  e  n3v3r  phase3
+} none
+foreach x cases [print [x  numeric? x  pnumeric? x]]