Fix adding Opts with | to lvalue Parser

This is the recommended way of adding new Opts in our documentation
for using custom main, but we did not compile the code to see if it
works. We now compile the example as part of the BUILD_EXAMPLES
option.

Fixes #2787

1 files changed, 3 insertions, 1 deletions

diff --git a/src/catch2/internal/catch_clara.hpp b/src/catch2/internal/catch_clara.hpp
index b7001db2..d869593b 100644
--- a/src/catch2/internal/catch_clara.hpp
+++ b/src/catch2/internal/catch_clara.hpp
@@ -673,7 +673,9 @@ namespace Catch {
 
             template <typename T>
             friend Parser operator|( Parser const& p, T&& rhs ) {
-                return Parser( p ) |= CATCH_FORWARD(rhs);
+                Parser temp( p );
+                temp |= rhs;
+                return temp;
             }
 
             template <typename T>