Substitute variable in template filename

README.md

@@ -289,7 +289,7 @@ The following table contains a list of all definitions, with the item each affec
 | data | sprite | key, value | Adds a user defined data entry to a sprite. |
 | **description** | - | filename | Adds an additional location where the output description should be written. When the _filename_ is a sequence e.g. `"slice{0-}.plist"` then each _slice_ is output to a separate file. |
 | template | description | filename | Sets the template which should be used for generating the output description. |
-| set | - | key, value | Sets a variable value, which can be accessed in different places using `{{key}}`. See a list of existing [variables](#variables). |
+| set | - | key, value | Sets a variable value, which can be accessed in strings and templates using `{{key}}`. See a list of existing [variables](#variables). |
 | group | - | - | Can be used for opening a new scope, to limit for example the effect of a tag. |
 
 <a id="definition-reference-end"></a>

src/common.cpp

@@ -431,6 +431,36 @@ void replace_variables(std::string& expression,
   }
 }
 
+void replace_variables(std::string& expression, const VariantMap& variables) {
+  const auto replace_variable = [&](std::string_view variable) {
+    if (auto it = variables.find(variable); it != variables.end())
+      return variant_to_string(it->second);
+    error("unknown id '", variable, "'");
+  };
+  return replace_variables(expression, replace_variable);
+}
+
+void replace_variables(std::filesystem::path& path, const VariantMap& variables) {
+  auto string = path_to_utf8(path);
+  replace_variables(string, variables);
+  path = utf8_to_path(string);
+}
+
+std::string variant_to_string(const Variant& variant) {
+  auto string = std::string();
+  std::visit([&](const auto& value) {
+    using T = std::decay_t<decltype(value)>;
+    if constexpr (std::is_same_v<T, std::string>) {
+      string = value;
+    }
+    else {
+      using namespace std;
+      string = to_string(value);
+    }
+  }, variant);
+  return string;
+}
+
 std::string make_identifier(std::string string) {
   for (auto& c : string)
     if (!is_alpha(c) && !is_digit(c))

src/common.h

@@ -12,11 +12,16 @@
 #include <utility>
 #include <optional>
 #include <cassert>
+#include <variant>
+#include <map>
 
 extern Scheduler scheduler;
 
 namespace spright {
 
+using Variant = std::variant<bool, real, std::string>;
+using VariantMap = std::map<std::string, Variant, std::less<>>;
+
 struct LStringView : std::string_view {
   LStringView(std::string_view s) : std::string_view(s) { }
   LStringView(const char* s) : std::string_view(s) { }
@@ -123,6 +128,9 @@ std::string remove_directory(std::string filename, int keep_n = 0);
 bool has_supported_extension(std::string_view filename);
 void replace_variables(std::string& expression,
   const std::function<std::string(std::string_view)>& replace_function);
+void replace_variables(std::string& expression, const VariantMap& variables);
+void replace_variables(std::filesystem::path& path, const VariantMap& variables);
+std::string variant_to_string(const Variant& variant);
 std::string make_identifier(std::string string);
 
 inline int floor(int v, int q) { return (v / q) * q; };

src/input.h

@@ -4,8 +4,6 @@
 #include "settings.h"
 #include "FilenameSequence.h"
 #include <memory>
-#include <map>
-#include <variant>
 
 namespace spright {
 
@@ -14,8 +12,6 @@ using SheetPtr = std::shared_ptr<const struct Sheet>;
 using OutputPtr = std::shared_ptr<const struct Output>;
 using MapVectorPtr = std::shared_ptr<const std::vector<ImagePtr>>;
 using StringMap = std::map<std::string, std::string, std::less<>>;
-using Variant = std::variant<bool, real, std::string>;
-using VariantMap = std::map<std::string, Variant, std::less<>>;
 
 enum class AnchorX { left, center, right };
 enum class AnchorY { top, middle, bottom };

src/main.cpp

@@ -49,7 +49,7 @@ int main(int argc, const char* argv[]) try {
   }
 
   if (settings.mode != Mode::autocomplete) {
-    complete_description_definitions(settings, descriptions);
+    complete_description_definitions(settings, descriptions, variables);
 
     output_descriptions(settings, descriptions, 
       inputs, sprites, slices, textures, variables);

src/output.h

@@ -21,7 +21,8 @@ void evaluate_expressions(const Settings& settings,
 
 void complete_description_definitions(
   const Settings& settings,
-  std::vector<Description>& descriptions);
+  std::vector<Description>& descriptions,
+  const VariantMap& variables);
 
 std::string dump_description(
   const std::string& template_source,

src/output_description.cpp

@@ -216,21 +216,6 @@ namespace {
     return env;
   }
 
-  std::string variant_to_string(const Variant& variant) {
-    auto string = std::string();
-    std::visit([&](const auto& value) {
-      using T = std::decay_t<decltype(value)>;
-      if constexpr (std::is_same_v<T, std::string>) {
-        string = value;
-      }
-      else {
-        using namespace std;
-        string = to_string(value);
-      }
-    }, variant);
-    return string;
-  }
-
   void output_description(std::ostream& os,
       const std::filesystem::path& template_filename,
       const nlohmann::json& json) {
@@ -361,8 +346,10 @@ void evaluate_expressions(
     }
 }
 
-void complete_description_definitions(const Settings& settings, 
-    std::vector<Description>& descriptions) {
+void complete_description_definitions(const Settings& settings,
+    std::vector<Description>& descriptions,
+    const VariantMap& variables) {
+
   // ignore description in definition
   if (settings.mode == Mode::describe ||
       settings.mode == Mode::describe_input)
@@ -382,6 +369,10 @@ void complete_description_definitions(const Settings& settings,
       if (description.filename.string() != "stdout")
         description.filename = settings.output_path / description.filename;
 
+  // replace variables
+  for (auto& description : descriptions)
+    replace_variables(description.template_filename, variables);
+
   // also lookup templates in sub-directory
   for (auto& description : descriptions) {
     auto& template_filename = description.template_filename;