minor improvement for parsing of backslash in lexemes

jtc.cpp

@@ -2646,7 +2646,7 @@ void Jtc::walk_interleaved_(wlk_subscr Jtc::* subscriber) {
  }
  hwlk_ = move(ARY{STR{}});                                      // reset hwlk_ to init value
  // json.ns() may hold now the latest updated namespace while wns_ might not even have been
- // updated (e.g. when walk has ended as <>F, or out of iterations), thus require syncing 
+ // updated (e.g.: when walk has ended as <>F, or out of iterations), thus require syncing
  wns_[last_dwi_ptr_].sync_in(json().ns(), map_jnse::NsOpType::NsUpdate);
 
  is_multi_walk_ = opt()[CHR(OPT_WLK)].hits() > 1 or             // i.e. -w.. -w.., else (one -w..)

lib/Json.hpp

@@ -3529,7 +3529,8 @@ std::string Json::extract_lexeme_(std::string::const_iterator &si, char closing)
  std::string quoted{"\\"};                                      // replace quoted closing bracket
  quoted += closing;
  for(size_t p = lexeme.find(quoted); p != std::string::npos; p = lexeme.find(quoted, p))
-  lexeme.replace(p, 2, 1, closing);
+  if(p + quoted.size() >= lexeme.size()) break;                 // replace only if it's not last
+  else lexeme.replace(p, 2, 1, closing);
  DBG(1) DOUT() << "parsed lexeme: " << lexeme << std::endl;
  return lexeme;
 }