Reduce code size of parseoptions.parse!int()

src/core/internal/parseoptions.d

@@ -168,6 +168,7 @@ inout(char)[] find(alias pred)(inout(char)[] str)
 }
 
 bool parse(T : size_t)(const(char)[] optname, ref inout(char)[] str, ref T res, const(char)[] errName, bool mayHaveSuffix = false)
+if (is(T == size_t))
 in { assert(str.length); }
 do
 {
@@ -242,6 +243,22 @@ do
     if (v > res.max)
         return parseError("a number " ~ T.max.stringof ~ " or below", optname, str[0 .. i], errName);
     str = str[i .. $];
+    res = v;
+    return true;
+}
+
+bool parse(T : size_t)(const(char)[] optname, ref inout(char)[] str, ref T res, const(char)[] errName, bool mayHaveSuffix = false)
+if (!is(T == size_t))
+in { assert(str.length); }
+do
+{
+    const oldStr = str;
+    size_t v;
+    if (!parse!size_t(optname, str, v, errName, mayHaveSuffix))
+        return false;
+
+    if (v > res.max)
+        return parseError("a number " ~ T.max.stringof ~ " or below", optname, oldStr[0 .. $-str.length], errName);
     res = cast(T) v;
     return true;
 }