fix: add a workaround for redeclaration

1 files changed, 16 insertions, 0 deletions

diff --git a/examples/reassign.sfinae b/examples/reassign.sfinae
new file mode 100644
index 0000000..9863cae
--- /dev/null
+++ b/examples/reassign.sfinae
@@ -0,0 +1,16 @@
+// there is no assignment. to change x, undeclare it and declare it again
+// if the new value depends on the old one, park it in a second variable first,
+// because the old one is gone by the time you declare
+
+::declare<::name<'x'>, ::decltype(::difference<'F', 'A'>)>::commit;
+::emit<::decltype(::value_of<::name<'x'>>)>::commit;
+
+::declare<
+    ::name<'n', 'e', 'x', 't'>,
+    ::decltype(::sum<::value_of<::name<'x'>>, ::difference<'B', 'A'>>)
+>::commit;
+::undeclare<::name<'x'>>::commit;
+::declare<::name<'x'>, ::decltype(::value_of<::name<'n', 'e', 'x', 't'>>)>::commit;
+::undeclare<::name<'n', 'e', 'x', 't'>>::commit;
+
+::emit<::decltype(::value_of<::name<'x'>>)>::commit;