Support for the confutils pragmas in the cli API.

This works around the fact that Nim doesn't support custom pragmas
for proc params at the moment by removing them from the AST.

confutils.nim

@@ -86,6 +86,12 @@ proc parseCmdArg*(T: type SomeSignedInt, s: TaintedString): T =
 proc parseCmdArg*(T: type SomeUnsignedInt, s: TaintedString): T =
   T parseUInt(string s)
 
+proc parseCmdArg*(T: type SomeFloat, p: TaintedString): T =
+  result = parseFloat(p)
+
+proc parseCmdArg*(T: type bool, p: TaintedString): T =
+  result = parseBool(p)
+
 proc parseCmdArg*(T: type enum, s: TaintedString): T =
   parseEnum[T](string(s))
 
@@ -331,9 +337,8 @@ proc dispatchImpl(cliProcSym, cliArgs, loadArgs: NimNode): NimNode =
     # Turn any default parameters into the confutils's `defaultValue` pragma
     if arg[2].kind != nnkEmpty:
       if arg[0].kind != nnkPragmaExpr:
-        arg[0] = newTree(nnkPragmaExpr, arg[0])
-      arg[0].add newTree(nnkPragma,
-                         newColonExpr(bindSym"defaultValue", arg[2]))
+        arg[0] = newTree(nnkPragmaExpr, arg[0], newTree(nnkPragma))
+      arg[0][1].add newColonExpr(bindSym"defaultValue", arg[2])
       arg[2] = newEmptyNode()
 
     configFields.add arg
@@ -383,5 +388,11 @@ macro cli*(args: varargs[untyped]): untyped =
 
   # Generate the final code
   result = newStmtList(cliProc, dispatchImpl(cliProcName, cliProc.params, args))
+
+  # TODO: remove this once Nim supports custom pragmas on proc params
+  for p in cliProc.params:
+    if p.kind == nnkEmpty: continue
+    p[0] = skipPragma p[0]
+
   debugMacroResult "CLI Code"