From 0595c7c74e3806f5e1783e9d6dc361543aee3c63 Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Tue, 18 Jun 2024 17:23:32 -0400
Subject: [PATCH] xo-expression: refactor: enforce Lambda.argv must contain
 Variables

---
 include/xo/expression/Lambda.hpp | 11 ++++++-----
 src/expression/Lambda.cpp        |  4 ++--
 2 files changed, 8 insertions(+), 7 deletions(-)

diff --git a/include/xo/expression/Lambda.hpp b/include/xo/expression/Lambda.hpp
index ed88b44e..cdf72ed9 100644
--- a/include/xo/expression/Lambda.hpp
+++ b/include/xo/expression/Lambda.hpp
@@ -6,6 +6,7 @@
 #pragma once
 
 #include "Expression.hpp"
+#include "Variable.hpp"
 #include <vector>
 #include <string>
 //#include <cstdint>
@@ -24,7 +25,7 @@ namespace xo {
              *  @p body   Expression for body of this function
              **/
             static ref::rp<Lambda> make(const std::string & name,
-                                        const std::vector<ref::rp<Expression>> & argv,
+                                        const std::vector<ref::rp<Variable>> & argv,
                                         const ref::rp<Expression> & body);
 
             /** downcast from Expression **/
@@ -34,7 +35,7 @@ namespace xo {
 
             const std::string & name() const { return name_; }
             const std::string & type_str() const { return type_str_; }
-            const std::vector<ref::rp<Expression>> & argv() const { return argv_; }
+            const std::vector<ref::rp<Variable>> & argv() const { return argv_; }
             const ref::rp<Expression> & body() const { return body_; }
 
             /** return number of arguments expected by this function **/
@@ -50,7 +51,7 @@ namespace xo {
              **/
             Lambda(const std::string & name,
                    TypeDescr lambda_type,
-                   const std::vector<ref::rp<Expression>> & argv,
+                   const std::vector<ref::rp<Variable>> & argv,
                    const ref::rp<Expression> & body);
 
         private:
@@ -67,14 +68,14 @@ namespace xo {
              **/
             std::string type_str_;
             /** formal argument names **/
-            std::vector<ref::rp<Expression>> argv_;
+            std::vector<ref::rp<Variable>> argv_;
             /** function body **/
             ref::rp<Expression> body_;
         }; /*Lambda*/
 
         inline ref::rp<Lambda>
         make_lambda(const std::string & name,
-                    const std::vector<ref::rp<Expression>> & argv,
+                    const std::vector<ref::rp<Variable>> & argv,
                     const ref::rp<Expression> & body)
         {
             return Lambda::make(name, argv, body);
diff --git a/src/expression/Lambda.cpp b/src/expression/Lambda.cpp
index acc40cbe..d92ac801 100644
--- a/src/expression/Lambda.cpp
+++ b/src/expression/Lambda.cpp
@@ -14,7 +14,7 @@ namespace xo {
     namespace ast {
         rp<Lambda>
         Lambda::make(const std::string & name,
-                     const std::vector<rp<Expression>> & argv,
+                     const std::vector<rp<Variable>> & argv,
                      const ref::rp<Expression> & body)
         {
             using xo::reflect::FunctionTdx;
@@ -47,7 +47,7 @@ namespace xo {
 
         Lambda::Lambda(const std::string & name,
                        TypeDescr lambda_type,
-                       const std::vector<rp<Expression>> & argv,
+                       const std::vector<rp<Variable>> & argv,
                        const ref::rp<Expression> & body)
             : Expression(exprtype::lambda, lambda_type),
               name_{name},