feat: scaffold crate structure and implement core macros

Add the project skeleton, LICENSE files, README, Makefile, doc
examples, and the initial implementation of `#[func]`, `invoke!`,
and `select!` procedural macros.

1 files changed, 3 insertions, 0 deletions

diff --git a/doc/usage/select.rs b/doc/usage/select.rs
new file mode 100644
index 0000000..8cffcf8
--- /dev/null
+++ b/doc/usage/select.rs
@@ -0,0 +1,3 @@
+fn example() {
+    select! [{ 100 } else { 200 }];
+}