Add predefined character class \D (no digit)

Matches every character except digits (`0` to `9`).

In PureBasic this means:

- `Chr(1)` to `Chr(47)`

- `Chr(58)` to `Chr(65535)`

Close #23

RegExEngine.pbi

@@ -280,6 +280,44 @@ Module RegEx
     ProcedureReturn *base
   EndProcedure
 
+  Procedure CreateNfaNoDigits(*regExEngine)
+    Protected *base, *nfa1, *nfa2
+    Protected i
+
+    ; Chr(1) to Chr(47)
+    ; Chr(58) to Chr(65535)
+
+    ; nfa1      nfa2
+    ; [1-47]    [0]
+    ; [58-255]  [0]
+
+    *nfa1 = CreateNfaSymbol(*regExEngine, 1)
+    For i = 2 To 47
+      *nfa1 = CreateNfaUnion(*regExEngine, *nfa1, CreateNfaSymbol(*regExEngine, i))
+    Next
+    For i = 58 To 255
+      *nfa1 = CreateNfaUnion(*regExEngine, *nfa1, CreateNfaSymbol(*regExEngine, i))
+    Next
+    *nfa2 = CreateNfaSymbol(*regExEngine, 0)
+    *base = CreateNfaConcatenation(*regExEngine, *nfa1, *nfa2)
+
+    ; nfa1     nfa2
+    ; [0-255]  [1-255]
+
+    *nfa1 = CreateNfaSymbol(*regExEngine, 0)
+    For i = 1 To 255
+      *nfa1 = CreateNfaUnion(*regExEngine, *nfa1, CreateNfaSymbol(*regExEngine, i))
+    Next
+    *nfa2 = CreateNfaSymbol(*regExEngine, 1)
+    For i = 2 To 255
+      *nfa2 = CreateNfaUnion(*regExEngine, *nfa2, CreateNfaSymbol(*regExEngine, i))
+    Next
+    *base = CreateNfaUnion(*regExEngine, *base,
+                           CreateNfaConcatenation(*regExEngine, *nfa1, *nfa2))
+
+    ProcedureReturn *base
+  EndProcedure
+
   Procedure CreateNfaWhiteSpace(*regExEngine)
     Protected *base, *nfa1, *nfa2
 
@@ -383,6 +421,9 @@ Module RegEx
           Case 'd'
             *regExString\currentPosition + SizeOf(Unicode)
             ProcedureReturn CreateNfaDigits(*regExEngine)
+          Case 'D'
+            *regExString\currentPosition + SizeOf(Unicode)
+            ProcedureReturn CreateNfaNoDigits(*regExEngine)
           Case 's'
             *regExString\currentPosition + SizeOf(Unicode)
             ProcedureReturn CreateNfaWhiteSpace(*regExEngine)