xo-reader xo-expression: nested lambdas working properly + docs

xo-expression/src/expression/Apply.cpp

@@ -58,6 +58,14 @@ namespace xo {
                                {lhs, rhs});
         }
 
+        void
+        Apply::attach_envs(bp<Environment> p) {
+            fn_->attach_envs(p);
+
+            for (const auto & arg : argv_)
+                arg->attach_envs(p);
+        }
+
         void
         Apply::display(std::ostream & os) const {
             os << "<Apply"