From cd2d1a04d8914f5e1797a487d035c89f4a76d481 Mon Sep 17 00:00:00 2001
From: Book-reader <thevoid@outlook.co.nz>
Date: Fri, 16 Jan 2026 10:26:18 +1300
Subject: [PATCH] Use a `Printable` struct for ansi rgb formatting instead of
 explicit allocations (#2696)

* Use a `Printable` struct for ansi rgb formatting

* update release notes

* Some renaming.

---------

Co-authored-by: Christoffer Lerno <christoffer@aegik.com>
---
 lib/std/core/ansi.c3          | 40 +++++++++++++++++++++++++++++++----
 releasenotes.md               |  1 +
 test/unit/stdlib/core/ansi.c3 |  7 +++---
 3 files changed, 41 insertions(+), 7 deletions(-)

diff --git a/lib/std/core/ansi.c3 b/lib/std/core/ansi.c3
index cedb703d4..68ffe7767 100644
--- a/lib/std/core/ansi.c3
+++ b/lib/std/core/ansi.c3
@@ -1,4 +1,5 @@
 module std::core::string::ansi;
+import std::io;
 
 enum Ansi : const inline String
 {
@@ -56,6 +57,37 @@ enum Ansi : const inline String
 	BG_BRIGHT_WHITE    = "\e[107m",
 }
 
+struct AnsiColor (Printable)
+{
+	char r, g, b;
+	bool bg;
+}
+
+fn usz? AnsiColor.to_format(&self, Formatter* fmt) @dynamic
+{
+	return fmt.printf("\e[%s8;2;%s;%s;%sm", self.bg ? 4 : 3, self.r, self.g, self.b);
+}
+
+<*
+ 24-bit color code
+
+ @return `A struct that, when formatted with '%s', sets the foreground or background colour to the specified rgb value`
+*>
+fn AnsiColor get_color_rgb(char r, char g, char b, bool bg = false)
+{
+	return {r, g, b, bg};
+}
+
+<*
+ 24-bit color code
+
+ @return `A struct that, when formatted with '%s', sets the foreground or background colour of printed text to the specified rgb value`
+*>
+fn AnsiColor get_color(uint rgb, bool bg = false)
+{
+	return {(char)(rgb >> 16), (char)((rgb & 0x00FF00) >> 8), (char)rgb, bg};
+}
+
 <*
  8-bit color code
 
@@ -96,7 +128,7 @@ macro String color(uint $rgb, bool $bg = false) @const
  @require rgb <= 0xFF_FF_FF : `Expected a 24 bit RGB value`
  @return `the string char for the given foreground color`
 *>
-fn String make_color(Allocator mem, uint rgb, bool bg = false)
+fn String make_color(Allocator mem, uint rgb, bool bg = false) @deprecated("use get_color instead")
 {
 	return make_color_rgb(mem, (char)(rgb >> 16), (char)((rgb & 0xFF00) >> 8), (char)rgb, bg);
 }
@@ -107,7 +139,7 @@ fn String make_color(Allocator mem, uint rgb, bool bg = false)
  @require rgb <= 0xFF_FF_FF : `Expected a 24 bit RGB value`
  @return `the string char for the given foreground color`
 *>
-fn String make_tcolor(uint rgb, bool bg = false)
+fn String make_tcolor(uint rgb, bool bg = false) @deprecated("use get_color instead")
 {
 	return make_color_rgb(tmem, (char)(rgb >> 16), (char)((rgb & 0xFF00) >> 8), (char)rgb, bg);
 }
@@ -117,7 +149,7 @@ fn String make_tcolor(uint rgb, bool bg = false)
 
  @return `the string char for the given foreground color`
 *>
-fn String make_color_rgb(Allocator mem, char r, char g, char b, bool bg = false)
+fn String make_color_rgb(Allocator mem, char r, char g, char b, bool bg = false) @deprecated("use get_color_rgb instead")
 {
 	return string::format(mem, "\e[%s8;2;%s;%s;%sm", bg ? 4 : 3, r, g, b);
 }
@@ -127,7 +159,7 @@ fn String make_color_rgb(Allocator mem, char r, char g, char b, bool bg = false)
 
  @return `the string char for the given foreground color`
 *>
-fn String make_tcolor_rgb(char r, char g, char b, bool bg = false)
+fn String make_tcolor_rgb(char r, char g, char b, bool bg = false) @deprecated("use get_color_rgb instead")
 {
 	return string::format(tmem, "\e[%s8;2;%s;%s;%sm", bg ? 4 : 3, r, g, b);
 }
diff --git a/releasenotes.md b/releasenotes.md
index 152f82523..68f053089 100644
--- a/releasenotes.md
+++ b/releasenotes.md
@@ -85,6 +85,7 @@
 - Add `streebog` (aka "GOST-12") hashing with 256-bit and 512-bit outputs. #2659
 - Add unit tests for HMAC 256 based on RFC 4231. #2743
 - Add extra `AsciiCharset` constants and combine its related compile-time/runtime macros. #2688
+- Use a `Printable` struct for ansi RGB formatting instead of explicit allocation and deprecate the old method.
 
 ## 0.7.8 Change list
 
diff --git a/test/unit/stdlib/core/ansi.c3 b/test/unit/stdlib/core/ansi.c3
index 8f36dda18..ffd9d3964 100644
--- a/test/unit/stdlib/core/ansi.c3
+++ b/test/unit/stdlib/core/ansi.c3
@@ -18,8 +18,9 @@ fn void test_color()
 	test::eq("\u001B[48;2;255;204;255m", ansi::color(0xFFCCFF, true));
 }
 
-fn void test_make_color()
+fn void test_get_color()
 {
-	test::eq("\u001B[38;2;255;204;255m", ansi::make_color(tmem, 0xFFCCFF));
-	test::eq("\u001B[48;2;255;204;255m", ansi::make_color(tmem, 0xFFCCFF, true));
+	test::eq("\u001B[38;2;255;204;254m", string::tformat("%s", ansi::get_color_rgb(0xFF, 0xCC, 0xFE)));
+	test::eq("\u001B[38;2;255;204;254m", string::tformat("%s", ansi::get_color(0xFFCCFE)));
+	test::eq("\u001B[48;2;255;204;254m", string::tformat("%s", ansi::get_color(0xFFCCFE, true)));
 }