[lldb] Refactor OptionValue to return a std::optional (NFC)

Refactor OptionValue to return a std::optional instead of taking a fail
value. This allows the caller to handle situations where there's no
value, instead of being unable to distinguish between the absence of a
value and the value happening the match the fail value. When a fail
value is required, std::optional::value_or() provides the same
functionality.

1 files changed, 3 insertions, 3 deletions

diff --git a/lldb/source/Interpreter/OptionValueArray.cpp b/lldb/source/Interpreter/OptionValueArray.cpp
index 40357d5f4b06..afd1f90aafe8 100644
--- a/lldb/source/Interpreter/OptionValueArray.cpp
+++ b/lldb/source/Interpreter/OptionValueArray.cpp
@@ -155,9 +155,9 @@ size_t OptionValueArray::GetArgs(Args &args) const {
   args.Clear();
   const uint32_t size = m_values.size();
   for (uint32_t i = 0; i < size; ++i) {
-    llvm::StringRef string_value = m_values[i]->GetStringValue();
-    if (!string_value.empty())
-      args.AppendArgument(string_value);
+    std::optional<llvm::StringRef> string_value = m_values[i]->GetStringValue();
+    if (string_value)
+      args.AppendArgument(*string_value);
   }
 
   return args.GetArgumentCount();