From c1c989d416a6ed749293e02694933f5208e7c554 Mon Sep 17 00:00:00 2001
From: Brett Laptop <tri11paragon@tpgc.me>
Date: Mon, 11 Dec 2023 16:58:20 -0500
Subject: [PATCH] love lambdas

---
 include/blt/std/utility.h | 13 +++++++++++++
 src/blt/std/format.cpp    | 37 +++++++++----------------------------
 2 files changed, 22 insertions(+), 28 deletions(-)

diff --git a/include/blt/std/utility.h b/include/blt/std/utility.h
index fcdb818..d05f4f6 100644
--- a/include/blt/std/utility.h
+++ b/include/blt/std/utility.h
@@ -208,6 +208,19 @@ namespace blt
                 return range_itr(_end - offset, offset == 0);
             }
     };
+    
+    template<class... TLambdas>
+    struct lambda_visitor : TLambdas... {
+        using TLambdas::operator()...;
+    };
+    
+#if __cplusplus < 202002L
+    
+    // explicit deduction guide (not needed as of C++20)
+    template<class... TLambdas>
+    lambda_visitor(TLambdas...) -> lambda_visitor<TLambdas...>;
+
+#endif
 
 
 #if defined(__GNUC__) || defined(__llvm__)
diff --git a/src/blt/std/format.cpp b/src/blt/std/format.cpp
index baf1b34..82a59f6 100755
--- a/src/blt/std/format.cpp
+++ b/src/blt/std/format.cpp
@@ -8,6 +8,7 @@
 #include <cmath>
 #include "blt/std/logging.h"
 #include "blt/std/assert.h"
+#include "blt/std/utility.h"
 #include <stack>
 #include <queue>
 #include <algorithm>
@@ -422,32 +423,6 @@ std::string blt::string::createPadding(size_t length, char spacing)
 namespace blt
 {
     
-    struct getHeight
-    {
-        inline size_t operator()(const blt::string::ascii_box& box)
-        {
-            return box.height();
-        }
-        
-        inline size_t operator()(const blt::string::ascii_boxes& boxes)
-        {
-            return boxes.height();
-        }
-    };
-    
-    struct getWidth
-    {
-        inline size_t operator()(const blt::string::ascii_box& box)
-        {
-            return box.width();
-        }
-        
-        inline size_t operator()(const blt::string::ascii_boxes& boxes)
-        {
-            return boxes.width();
-        }
-    };
-    
     void constructVerticalSeparator(blt::string::ascii_data& data, size_t offset, size_t height)
     {
         for (size_t i = 0; i < height; i++)
@@ -491,8 +466,14 @@ namespace blt
     
     blt::string::ascii_data blt::string::constructBox(const blt::string::box_type& box)
     {
-        auto width = std::visit(getWidth(), box);
-        auto height = std::visit(getHeight(), box);
+        auto width = std::visit(blt::lambda_visitor{
+                [](const blt::string::ascii_box& box) -> size_t {return box.width();},
+                [](const blt::string::ascii_boxes& boxes) -> size_t {return boxes.width();}
+            }, box);
+        auto height = std::visit(blt::lambda_visitor{
+                [](const blt::string::ascii_box& box) -> size_t {return box.height();},
+                [](const blt::string::ascii_boxes& boxes) -> size_t {return boxes.height();}
+            }, box);
         
         string::ascii_data data(width, height);