Out of range error in prompt example for ENTER input

terminate called after throwing an instance of 'std::out_of_range' 1,1 ] what(): basic_string::substr: __pos (which is 18446744073709551615) > this->size() (which is 1) gdb: 0x00005555555575da in determine_completeness (command="\n") at /home/awvwgk/projects/src/git/cpp-terminal/examples/prompt.cpp:15

Author: awvwgk

examples/prompt.cpp

@@ -12,7 +12,7 @@ using Term::Terminal;
 bool determine_completeness([[maybe_unused]] std::string command) {
  // Determine if the statement is complete
  bool complete;
- if (command.substr(command.size() - 2, 1) == "\\") {
+ if (command.size() > 1 && command.substr(command.size() - 2, 1) == "\\") {
  complete = false;
  } else {
  complete = true;