Initial commit: Klammertext source distribution

Curated source subset assembled by klammertext-dev's doc/make_dist.sh: the Klammermachine (mac), the Standard Klammer Set (sks), the commands (com), editor plugins and install guides (doc), a test subset (tst), and lib/bin placeholders. Builds with 'make -C com'.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

mac/locator.h

@@ -0,0 +1,52 @@
+#pragma once
+
+#include <iostream>
+#include <string>
+// #include <filesystem>
+#include <source_location>
+#include <map>
+
+#include "file.h"
+
+inline std::string klammertext_home_var = "KLAMMERTEXT_HOME";
+
+class Locator
+{
+public:
+    explicit Locator(const std::source_location location =
+                     std::source_location::current())
+        // std::source_location::file_name() can return nullptr on some
+        // toolchains (e.g. Homebrew GCC on macOS); guard against
+        // fs::path(nullptr) -> strlen(NULL).
+        : m_filename(location.file_name()
+                     ? fs::absolute(location.file_name()) : fs::path{})
+        , m_line(int(location.line()))
+        , m_chr(int(location.column()))
+        {};
+    Locator(fs::path filename, int line, int chr);
+    std::string str(bool relative = false) const;
+    std::string desc(bool relative = false) const;
+    std::string abbrev(bool include_chr=true) const;
+
+    std::string m_filename {};
+    int m_line;
+    int m_chr;
+    //std::string m_desc {};
+};
+
+std::ostream &nformat(std::ostream &os);
+
+std::string locator_range(
+    const Locator& start_loc, const Locator& end_loc,
+    std::map<std::string, std::string>& relpath);
+
+Locator current_locator(
+    const std::source_location location = std::source_location::current());
+
+std::string locator_summary(std::vector<Locator> locators);
+
+inline
+std::string showloc(Locator loc=Locator()) {
+    return loc.abbrev(false) + " ";
+}
+