Add contains method to ValueTokenizer

src/tokenizer.cpp

@@ -17,6 +17,7 @@
 
 #include "tokenizer.h"
 #include "utils.h"
+#include <algorithm>
 
 using namespace LAMMPS_NS;
 
@@ -84,6 +85,10 @@ bool ValueTokenizer::has_next() const {
     return current != tokens.cend();
 }
 
+bool ValueTokenizer::contains(const std::string & value) const {
+    return std::find(tokens.cbegin(), tokens.cend(), value) != tokens.cend();
+}
+
 std::string ValueTokenizer::next_string() {
     if (has_next()) {
         std::string value = *current;