libk: add some tests

- merge types.h and type_traits.h

1 files changed, 40 insertions, 0 deletions

diff --git a/libk/string/integerview.cc b/libk/string/integerview.cc
new file mode 100644
index 0000000..beeb561
--- /dev/null
+++ b/libk/string/integerview.cc
@@ -0,0 +1,40 @@
+#include <string.h>
+
+/* itoa:  convert n to characters in s */
+template <typename T, int base = 10>
+constexpr size_t itoa(T n, char s[]) {
+  const bool is_negative = (n < 0);
+  if constexpr (!is_unsigned<T>()) {
+    if (n < 0)
+      n = -n;
+  }
+
+  int i = 0;
+  do {                                     /* generate digits in reverse order */
+    s[i++] = "0123456789abcdef"[n % base]; /* get next digit */
+  } while ((n /= base) > 0);               /* delete it */
+
+  if (is_negative)
+    s[i++] = '-';
+
+  s[i] = '\0';
+
+  // reverse(s, i);
+  return i;
+}
+
+IntegerView::IntegerView(int32_t n) {
+  length = itoa(n, buffer);
+}
+
+IntegerView::IntegerView(HexFormat_int32 f) {
+  length = itoa<int32_t, 16>(f.n, buffer);
+  buffer[length++] = 'x';
+  buffer[length++] = '0';
+}
+
+IntegerView::IntegerView(HexFormat_uint32 f) {
+  length = itoa<uint32_t, 16>(f.n, buffer);
+  buffer[length++] = 'x';
+  buffer[length++] = '0';
+}