From 27a0dd591f7ca6454bbfd782bc9cd8ae863f44a4 Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Fri, 14 Jun 2024 16:11:37 -0400
Subject: [PATCH] xo-pyexpression: + Primitive + PrimitiveInterface + examples

---
 src/pyexpression/pyexpression.cpp | 33 +++++++++++++++++++++++++++++++
 1 file changed, 33 insertions(+)

diff --git a/src/pyexpression/pyexpression.cpp b/src/pyexpression/pyexpression.cpp
index a87f6b06..c42fbcc7 100644
--- a/src/pyexpression/pyexpression.cpp
+++ b/src/pyexpression/pyexpression.cpp
@@ -5,7 +5,10 @@
 #include "xo/expression/Expression.hpp"
 #include "xo/expression/ConstantInterface.hpp"
 #include "xo/expression/Constant.hpp"
+#include "xo/expression/PrimitiveInterface.hpp"
+#include "xo/expression/Primitive.hpp"
 #include "xo/pyutil/pyutil.hpp"
+#include <cmath>
 
 namespace xo {
     namespace ast {
@@ -13,6 +16,9 @@ namespace xo {
         using xo::ast::Expression;
         using xo::ast::ConstantInterface;
         using xo::ast::Constant;
+        using xo::ast::PrimitiveInterface;
+        using xo::ast::Primitive;
+        using xo::ast::make_primitive;
         using xo::reflect::TaggedPtr;
         using xo::ref::rp;
         namespace py = pybind11;
@@ -38,6 +44,8 @@ namespace xo {
                 .def("__repr__", &Expression::display_string);
             ;
 
+            // ----- Constants -----
+
             py::class_<ConstantInterface,
                        Expression,
                        rp<ConstantInterface>>(m, "ConstantInterface")
@@ -69,6 +77,31 @@ namespace xo {
                   py::doc("make_constant(x) creates constant expression holding x [wip - only works for double"))
                 ;
 
+            // ----- Primitives -----
+
+            py::class_<PrimitiveInterface,
+                Expression,
+                       rp<PrimitiveInterface>>(m, "PrimitiveInterface")
+                .def("name", &PrimitiveInterface::name,
+                     py::doc("name of this primitive function;  use this name to invoke the function"))
+                .def("n_arg", &PrimitiveInterface::n_arg,
+                     py::doc("number of arguments to this function (not counting return value)"))
+                ;
+
+            using Fn_dbl_dbl_type = double (*)(double);
+
+            m.def("make_sqrt_pm", []() { return make_primitive<Fn_dbl_dbl_type>("sqrt", sqrt); },
+                  py::doc("create primitive representing the ::sqrt() function"));
+            m.def("make_sin_pm", []() { return make_primitive<Fn_dbl_dbl_type>("sin", ::sin); },
+                  py::doc("create primitive representing the ::sin() function"));
+            m.def("make_cos_pm", []() { return make_primitive<Fn_dbl_dbl_type>("cos", ::cos); },
+                  py::doc("create primitive representing the ::cos() function"));
+
+            py::class_<Primitive<double (*)(double)>,
+                       PrimitiveInterface,
+                       rp<Primitive<double (*)(double)>>>(m, "Primitive_double_double")
+                ;
+
         } /*pyexpresion*/
     } /*namespace ast*/
 } /*namespace xo*/