[features] Feature array, a special case of contiguous string array for adding namespaced features in CRF-like sequence models

src/features.h

@@ -0,0 +1,22 @@
+#ifndef FEATURES_H
+#define FEATURES_H
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdio.h>
+#include <stdarg.h>
+#include "string_utils.h"
+
+#define FEATURE_SEPARATOR_CHAR "|"
+
+void feature_array_add(char_array *features, int num_args, ...);
+
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif