implement shorthands

Author: Tsche

include/rsl/cli/annotations.hpp

@@ -43,5 +43,4 @@ struct Shorthand : _impl::StringAnnotation {
 struct Description : _impl::StringAnnotation {
     using _impl::StringAnnotation::StringAnnotation;
 };
-
 }  // namespace rsl::annotations

include/rsl/cli/option.hpp

@@ -1,5 +1,6 @@
 #pragma once
 #include <meta>
+#include <rsl/constexpr_assert>
 #include <rsl/meta_traits>
 #include <vector>
 #include <string_view>
@@ -104,19 +105,32 @@ struct Option {
   rsl::string_view name;
   rsl::string_view description;
   rsl::span<Parameter const> parameters;
+  char shorthand = '\0';
   bool run_early = false;
   bool is_flag   = false;
 
   std::optional<Unevaluated> parse(ArgParser& parser) {
     auto opt_name = parser.current();
-    if (!opt_name.starts_with("--")) {
+    if (!opt_name.starts_with('-')) {
       return {};
     }
 
-    opt_name.remove_prefix(2);
-    if (opt_name != name) {
-      return {};
+    opt_name.remove_prefix(1);
+    if (!opt_name.starts_with('-')) {
+      if (opt_name.size() != 1) {
+        return {};
+      }
+
+      if (opt_name[0] != shorthand) {
+        return {};
+      }
+    } else {
+      opt_name.remove_prefix(1);
+      if (opt_name != name) {
+        return {};
+      }
     }
+
     ++parser.cursor;  // parser will not unwind after this point
 
     Unevaluated option{.handle = _impl_handler};
@@ -152,6 +166,15 @@ struct Option {
       description = std::define_static_string(desc->data);
     }
 
+    if (auto shorthand_tag = annotation_of_type<annotations::Shorthand>(reflection);
+        shorthand_tag) {
+      auto short_opt = shorthand_tag->data;
+      if (short_opt.size() != 1) {
+        compile_error("Shorthands need to be a single character");
+      }
+      shorthand = short_opt[0];
+    }
+
     if (meta::has_annotation<annotations::Flag>(reflection)) {
       is_flag = true;
     }

include/rsl/cli/parser.hpp

@@ -35,7 +35,6 @@ T parse_value(std::string_view value) {
     // TODO move out of header
     std::string lower_value(value);
     std::ranges::transform(lower_value, lower_value.begin(), [](char c) {return std::tolower(c); });
-    std::println("{}", lower_value);
     if (lower_value == "1" || lower_value == "y" || lower_value == "yes" || lower_value == "on" ||
         lower_value == "true") {
       return true;

include/rsl/config

@@ -243,11 +243,10 @@ struct config {
 };
 
 struct cli {
-  static constexpr auto option     = annotations::option;
-  static constexpr auto positional = annotations::positional;
-  static constexpr auto value      = rsl::placeholders::_0;
-  static constexpr auto flag       = annotations::flag;
-
+  static constexpr auto option      = annotations::option;
+  static constexpr auto positional  = annotations::positional;
+  static constexpr auto value       = rsl::placeholders::_0;
+  static constexpr auto flag        = annotations::flag;
   using shorthand   = annotations::Shorthand;
   using description = annotations::Description;
 

src/cli.cpp

@@ -11,6 +11,10 @@ std::string& config::get_config_path() {
 void _cli_impl::print_help(_cli_impl::Spec const& spec,
                            std::string_view program_name,
                            std::string_view description) {
+  if (!description.empty()) {
+    std::println("{}", description);
+  }
+
   std::string arguments{};
   for (auto argument : spec.arguments) {
     if (argument.is_optional) {
@@ -21,10 +25,6 @@ void _cli_impl::print_help(_cli_impl::Spec const& spec,
   }
   std::println("usage: {} {}", program_name, arguments);
 
-  if (!description.empty()) {
-    std::println("\n{}", description);
-  }
-
   std::println("\nArguments:");
   for (auto argument : spec.arguments) {
     std::println("    {} -> {}", argument.name, argument.type);