From 73c1b54d5036cb87eaf615c78d34a733fe6b047b Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Wed, 24 Dec 2025 19:40:48 -0500
Subject: [PATCH] xo-facet: facet template [WIP]

---
 idl/Sequence.json5               | 47 ++++++++++++++++++++++++++++++++
 include/xo/object2/ASequence.hpp | 43 +++++++++++++++++++++++++++++
 2 files changed, 90 insertions(+)
 create mode 100644 idl/Sequence.json5
 create mode 100644 include/xo/object2/ASequence.hpp

diff --git a/idl/Sequence.json5 b/idl/Sequence.json5
new file mode 100644
index 0000000..a0dc001
--- /dev/null
+++ b/idl/Sequence.json5
@@ -0,0 +1,47 @@
+{
+    includes: ["<xo/gc/GCObject.hpp>"],
+    namespace1: "xo",
+    namespace2: "scm",
+    facet: "Sequence",
+    brief: "an ordered collection of variants",
+    doc: [
+        "Elements appear in some determinstic order.",
+        "Sequence is GC-aware --> elements must be GC-aware"
+    ],
+    methods: [
+        // bool is_empty() const noexcept
+        {
+            name: "is_empty",
+            doc: ["true iff sequence is empty"],
+            return_type: "bool",
+            args: [],
+            const: true,
+            noexcept: true,
+            attributes: [],
+        },
+
+        // bool is_finite() const noexcept
+        {
+            name: "is_finite",
+            doc: ["true iff sequence is finite"],
+            return_type: "bool",
+            args: [],
+            const: true,
+            noexcept: true,
+            attributes: [],
+        },
+
+        // obj<AGCObject> at(size_type index) const;
+        {
+            name: "at",
+            doc: ["return element @p index of this sequence"],
+            return_type: "obj<AGCObject>",
+            args: [
+                {type: "size_type", name: "index"},
+            ],
+            const: true,
+            noexcept: false,
+            attributes: [],
+        },
+    ],
+}
diff --git a/include/xo/object2/ASequence.hpp b/include/xo/object2/ASequence.hpp
new file mode 100644
index 0000000..db12e6b
--- /dev/null
+++ b/include/xo/object2/ASequence.hpp
@@ -0,0 +1,43 @@
+/** @file ASequence.hpp
+ *
+ *  Generated automagically from ingredients:
+ *  1. code generator:
+ *       [/home/roland/proj/xo-umbrella2/xo-object2/../xo-facet/codegen/genfacet.py]
+ *     arguments:
+ *       --input [./idl/Sequence.json5]
+ *  2. jinja2 template for abstract facet .hpp file:
+ *       [abstract_facet.hpp.j2]
+ *  3. idl for facet methods
+ *       [./idl/Sequence.json5]
+ **/
+
+#pragma once
+
+// includes (via {facet_includes})
+#include <xo/gc/GCObject.hpp>
+
+namespace xo {
+namespace scm {
+
+/**
+Elements appear in some determinstic order.
+Sequence is GC-aware --> elements must be GC-aware
+**/
+class ASequence {
+public:
+
+    /** true iff sequence is empty **/
+    virtual bool is_empty() const noexcept = 0;
+
+
+    /** true iff sequence is finite **/
+    virtual bool is_finite() const noexcept = 0;
+
+
+    /** return element @p index of this sequence **/
+    virtual obj<AGCObject> at(size_type index) const = 0;
+
+}; /*ASequence*/
+
+} /*namespace scm*/
+} /*namespace xo*/
\ No newline at end of file