From fa9f4967f2389619baa82b436b7031f1f5298594 Mon Sep 17 00:00:00 2001
From: Roland Conybeare <rconybeare@gmail.com>
Date: Mon, 19 Aug 2024 15:58:35 -0400
Subject: [PATCH] xo-reader: + parserstatemachine.push_exprstate(); simplify
 lambda_xs

---
 include/xo/reader/lambda_xs.hpp          |  2 +-
 include/xo/reader/parserstatemachine.hpp |  1 +
 src/reader/expect_expr_xs.cpp            |  7 +------
 src/reader/lambda_xs.cpp                 | 11 ++++-------
 src/reader/parserstatemachine.cpp        | 10 ++++++++++
 5 files changed, 17 insertions(+), 14 deletions(-)

diff --git a/include/xo/reader/lambda_xs.hpp b/include/xo/reader/lambda_xs.hpp
index 5ad0adfb..79c084ab 100644
--- a/include/xo/reader/lambda_xs.hpp
+++ b/include/xo/reader/lambda_xs.hpp
@@ -40,7 +40,7 @@ namespace xo {
         public:
             lambda_xs();
 
-            static void start(exprstatestack * p_stack, rp<Expression> * p_emit_expr);
+            static void start(parserstatemachine * p_psm);
 
             virtual void on_lambda_token(const token_type & tk,
                                          parserstatemachine * p_psm) override;
diff --git a/include/xo/reader/parserstatemachine.hpp b/include/xo/reader/parserstatemachine.hpp
index c5222194..c7ca130c 100644
--- a/include/xo/reader/parserstatemachine.hpp
+++ b/include/xo/reader/parserstatemachine.hpp
@@ -27,6 +27,7 @@ namespace xo {
 
             std::unique_ptr<exprstate> pop_exprstate();
             exprstate & top_exprstate();
+            void push_exprstate(std::unique_ptr<exprstate> x);
 
         public:
             exprstatestack * p_stack_;
diff --git a/src/reader/expect_expr_xs.cpp b/src/reader/expect_expr_xs.cpp
index bdd66b1a..2ec95272 100644
--- a/src/reader/expect_expr_xs.cpp
+++ b/src/reader/expect_expr_xs.cpp
@@ -41,13 +41,8 @@ namespace xo {
 
             //constexpr const char * self_name = "exprstate::on_leftparen";
 
-            auto p_stack = p_psm->p_stack_;
-            auto p_emit_expr = p_psm->p_emit_expr_;
-
             /* push lparen_0 to remember to look for subsequent rightparen. */
-            lambda_xs::start(p_stack, p_emit_expr);
-            //p_psm->top_exprstate().on_lambda_token(tk, p_stack, p_emit_expr);
-            //p_stack->push_exprstate(expect_expr_xs::expect_rhs_expression());
+            lambda_xs::start(p_psm);
         }
 
         void
diff --git a/src/reader/lambda_xs.cpp b/src/reader/lambda_xs.cpp
index 1ad6f401..491ab908 100644
--- a/src/reader/lambda_xs.cpp
+++ b/src/reader/lambda_xs.cpp
@@ -17,14 +17,11 @@ namespace xo {
         }
 
         void
-        lambda_xs::start(exprstatestack * p_stack,
-                         rp<Expression> * p_emit_expr)
+        lambda_xs::start(parserstatemachine * p_psm)
         {
-            parserstatemachine psm(p_stack, p_emit_expr);
-
-            p_stack->push_exprstate(lambda_xs::make());
-            p_stack->top_exprstate()
-                .on_lambda_token(token_type::lambda(), &psm);
+            p_psm->push_exprstate(lambda_xs::make());
+            p_psm->top_exprstate()
+                .on_lambda_token(token_type::lambda(), p_psm);
         }
 
         lambda_xs::lambda_xs() : exprstate(exprstatetype::lambdaexpr) {}
diff --git a/src/reader/parserstatemachine.cpp b/src/reader/parserstatemachine.cpp
index 6d47b909..103ac15b 100644
--- a/src/reader/parserstatemachine.cpp
+++ b/src/reader/parserstatemachine.cpp
@@ -12,6 +12,16 @@ namespace xo {
         parserstatemachine::pop_exprstate() {
             return p_stack_->pop_exprstate();
         }
+
+        exprstate &
+        parserstatemachine::top_exprstate() {
+            return p_stack_->top_exprstate();
+        }
+
+        void
+        parserstatemachine::push_exprstate(std::unique_ptr<exprstate> x) {
+            p_stack_->push_exprstate(std::move(x));
+        }
     } /*namespace scm*/
 } /*namespace xo*/