Update wcwidth implementation for Windows and add a binding library

src/modules/module_wcwidth.c

@@ -0,0 +1,32 @@
+#include <kuroko/vm.h>
+#include <kuroko/util.h>
+
+#include <wchar.h>
+#include <locale.h>
+
+#ifndef _WIN32
+extern int wcwidth(wchar_t c);
+#else
+static
+#include "../wcwidth._h"
+#endif
+
+KRK_FUNC(wcwidth,{
+	FUNCTION_TAKES_EXACTLY(1);
+	CHECK_ARG(0,int,krk_integer_type,codepoint);
+	return INTEGER_VAL(wcwidth(codepoint));
+})
+
+KrkValue krk_module_onload_wcwidth(void) {
+	KrkInstance * module = krk_newInstance(vm.baseClasses->moduleClass);
+	krk_push(OBJECT_VAL(module));
+	KRK_DOC(module, "Character widths.");
+	BIND_FUNC(module, wcwidth);
+
+#ifndef _WIN32
+	setlocale(LC_ALL, "");
+#endif
+
+	return krk_pop();
+}
+

test.krk

@@ -0,0 +1,16 @@
+import math
+import random
+
+def calcPi():
+    let inside = 0
+    let total = 0
+    for i = 0; i < 1000000; i++:
+        let x = random.random()
+        let y = random.random()
+        if x * x + y * y <= 1.0:
+            inside += 1
+        total += 1
+    print('pi = ', 4.0 * (inside / total))
+
+calcPi()
+