Barely working ansi color codes parser but I _really_ don't like this one. Too much code to just get it to process correctly which means it'll be brittle as hell later.

ansi_parser.rl

@@ -0,0 +1,99 @@
+#include <fmt/core.h>
+#include <string_view>
+#include <charconv>
+#include "dbc.hpp"
+
+using namespace fmt;
+
+%%{
+  machine foo;
+
+  action tstart {
+    start = fpc;
+  }
+
+  action number {
+    auto [ptr, ec] = std::from_chars(start, fpc, value);
+    dbc::check(ec == std::errc(), "error in number parsing");
+    println("NUM: {}", value);
+  }
+
+  action color256 {
+    println("COLOR256");
+  }
+
+  action color24b {
+    println("COLOR24B");
+  }
+
+  action colorSingle {
+    println("SINGLE");
+  }
+
+  action colorBasic {
+    println("BASIC");
+  }
+
+  action bg {
+    println("BG");
+  }
+
+  action fg {
+    println("FG");
+  }
+
+  action any {
+    println("ANY: {}:{}", int(fc), fc);
+  }
+
+  action start {
+    println("START");
+  }
+
+  action end {
+    println("END");
+  }
+
+  start = 0x1B "[";
+  fg = "38;" %fg;
+  bg = "48;" %bg;
+  num = digit+ >tstart %number;
+  color256 = "5;" num ";" num;
+  color24b = "2;" num ";" num ";" num;
+  basic = num ";" num;
+  single = num;
+
+  colorCode = (
+      start %start
+      (
+        (fg|bg) color256 %color256 |
+        (fg|bg) color24b %color24b |
+        single %colorSingle |
+        basic %colorBasic
+      )**
+      "m" %end
+  );
+
+  other = (any+ @any -- 0x1B)*;
+
+  main := (other :>> colorCode)**;
+}%%
+
+%% write data;
+
+bool parse_ansi(std::string_view codes) {
+  const char *start = NULL;
+  int cs = 0;
+  size_t value = 0;
+  const char *p = codes.data();
+  const char *pe = p + codes.size();
+  const char *eof = pe;
+
+
+  %% write init;
+  %% write exec;
+
+  print("PROCESSED {} CHARS of {}", p - codes.data(), codes.size());
+
+  return true;
+}