Introduced integrated documentation for builtin functions

musique/interpreter/builtin_function_documentation.hh

@@ -0,0 +1,9 @@
+#ifndef MUSIQUE_BUILTIN_FUNCTION_DOCUMENTATION_HH
+#define MUSIQUE_BUILTIN_FUNCTION_DOCUMENTATION_HH
+
+#include <optional>
+#include <string_view>
+
+std::optional<std::string_view> find_documentation_for_builtin(std::string_view builtin_name);
+
+#endif

musique/main.cc

@@ -17,6 +17,7 @@
 #include <musique/try.hh>
 #include <musique/unicode.hh>
 #include <musique/value/block.hh>
+#include <musique/interpreter/builtin_function_documentation.hh>
 
 #ifdef _WIN32
 extern "C" {
@@ -418,6 +419,20 @@ static std::optional<Error> Main(std::span<char const*> args)
 			return {};
 		}
 
+		if (arg == "--doc" || arg == "-d") {
+			if (args.empty()) {
+				std::cerr << "musique: error: option " << arg << " requires an argument" << std::endl;
+				std::exit(1);
+			}
+			if (auto maybe_docs = find_documentation_for_builtin(pop(args)); maybe_docs) {
+				std::cout << *maybe_docs << std::endl;
+				return {};
+			} else {
+				std::cerr << "musique: error: cannot find documentation for given builtin" << std::endl;
+				std::exit(1);
+			}
+		}
+
 		if (arg == "-h" || arg == "--help") {
 			usage();
 		}

scripts/build.mk

@@ -1,4 +1,4 @@
-Release_Obj=$(addprefix bin/$(os)/,$(Obj))
+Release_Obj=$(addprefix bin/$(os)/,$(Obj)) bin/$(os)/builtin_function_documentation.o
 
 bin/$(os)/bestline.o: lib/bestline/bestline.c lib/bestline/bestline.h
 	@echo "CC $@"
@@ -12,7 +12,14 @@ bin/$(os)/$(Target): $(Release_Obj) bin/$(os)/main.o bin/$(os)/rtmidi.o $(Bestli
 	@echo "CXX $@"
 	@$(CXX) $(CXXFLAGS) $(RELEASE_FLAGS) $(CPPFLAGS) -o $@ $(Release_Obj) bin/$(os)/rtmidi.o $(Bestline) $(LDFLAGS) $(LDLIBS)
 
-Debug_Obj=$(addprefix bin/$(os)/debug/,$(Obj))
+bin/$(os)/builtin_function_documentation.o: bin/$(os)/builtin_function_documentation.cc
+	@echo "CXX $@"
+	@$(CXX) $(CXXFLAGS) $(RELEASE_FLAGS) $(CPPFLAGS) -o $@ $< -c
+
+bin/$(os)/builtin_function_documentation.cc: musique/interpreter/builtin_functions.cc scripts/document-builtin.py
+	scripts/document-builtin.py -f cpp -o $@ musique/interpreter/builtin_functions.cc
+
+Debug_Obj=$(addprefix bin/$(os)/debug/,$(Obj)) bin/$(os)/debug/builtin_function_documentation.o
 
 bin/$(os)/debug/$(Target): $(Debug_Obj) bin/$(os)/debug/main.o bin/$(os)/rtmidi.o $(Bestline)
 	@echo "CXX $@"
@@ -22,3 +29,6 @@ bin/$(os)/debug/%.o: musique/%.cc
 	@echo "CXX $@"
 	@$(CXX) $(CXXFLAGS) $(DEBUG_FLAGS) $(CPPFLAGS) -o $@ $< -c
 
+bin/$(os)/debug/builtin_function_documentation.o: bin/$(os)/builtin_function_documentation.cc
+	@echo "CXX $@"
+	@$(CXX) $(CXXFLAGS) $(DEBUG_FLAGS) $(CPPFLAGS) -o $@ $< -c

scripts/document-builtin.py

@@ -1,11 +1,12 @@
 #!/usr/bin/env python3
 import argparse
 import dataclasses
-import string
-import re
 import itertools
-import typing
+import json
+import re
+import string
 import subprocess
+import typing
 
 MARKDOWN_CONVERTER = "lowdown -m 'shiftheadinglevelby=3'"
 CPP_FUNC_IDENT_ALLOWLIST = string.ascii_letters + string.digits + "_"
@@ -60,6 +61,16 @@ HTML_SUFFIX = """
 </html>
 """
 
+FIND_DOCUMENTATION_FOR_BUILTIN = """
+std::optional<std::string_view> find_documentation_for_builtin(std::string_view builtin_name)
+{
+	for (auto [name, doc] : names_to_documentation) {
+		if (builtin_name == name)
+			return doc;
+	}
+	return std::nullopt;
+}
+"""
 
 def warning(*args, prefix: str | None = None):
     if prefix is None:
@@ -151,7 +162,9 @@ def builtins_from_file(source_path: str) -> typing.Generator[Builtin, None, None
         yield builtin
 
 
-def filter_builtins(builtins: list[Builtin]) -> typing.Generator[Builtin, None, None]:
+def filter_builtins(
+    builtins: typing.Iterable[Builtin],
+) -> typing.Generator[Builtin, None, None]:
     for builtin in builtins:
         if not builtin.documentation:
             warning(f"builtin '{builtin.implementation}' doesn't have documentation")
@@ -167,7 +180,7 @@ def filter_builtins(builtins: list[Builtin]) -> typing.Generator[Builtin, None,
 def each_musique_name_occurs_once(
     builtins: typing.Iterable[Builtin],
 ) -> typing.Generator[Builtin, None, None]:
-    names = {}
+    names: dict[str, str] = {}
     for builtin in builtins:
         for name in builtin.names:
             if name in names:
@@ -178,7 +191,7 @@ def each_musique_name_occurs_once(
         yield builtin
 
 
-def generate_html_document(builtins: list[Builtin], output_path: str):
+def generate_html_document(builtins: typing.Iterable[Builtin], output_path: str):
     with open(output_path, "w") as out:
         out.write(HTML_PREFIX)
 
@@ -218,7 +231,40 @@ def generate_html_document(builtins: list[Builtin], output_path: str):
         out.write(HTML_SUFFIX)
 
 
-def main(source_path: str, output_path: str):
+def generate_cpp_documentation(builtins: typing.Iterable[Builtin], output_path: str):
+    # TODO Support markdown rendering and colors using `pretty` sublibrary
+
+    def documentation_str_var(builtin: Builtin):
+        return f"{builtin.implementation}_doc"
+
+    with open(output_path, "w") as out:
+        print("#include <array>", file=out)
+        print("#include <musique/interpreter/builtin_function_documentation.hh>\n", file=out)
+
+        # 1. Generate strings with documentation
+        for builtin in builtins:
+            # FIXME json.dumps will probably produce valid C++ strings for most cases,
+            # but can we ensure that will output valid strings for all cases?
+            print(
+                "static constexpr std::string_view %s = %s;"
+                % (documentation_str_var(builtin), json.dumps(builtin.documentation)),
+                file=out,
+            )
+        print("", file=out)
+
+        # 2. Generate array mapping from name to documentation variable
+        names_to_documentation = list(sorted((name, documentation_str_var(builtin)) for builtin in builtins for name in builtin.names))
+        print("static constexpr std::array<std::pair<std::string_view, std::string_view>, %d> names_to_documentation = {" % (len(names_to_documentation), ), file=out)
+        for name, doc in names_to_documentation:
+              print("  std::pair { std::string_view(%s), %s }," % (json.dumps(name), doc), file=out)
+        print("};", file=out);
+
+        # 3. Generate function that given builtin name results in documentation string
+        print(FIND_DOCUMENTATION_FOR_BUILTIN, file=out)
+
+
+
+def main(source_path: str, output_path: str, format: typing.Literal["html", "cpp"]):
     "Generates documentaiton from file source_path and saves in output_path"
 
     builtins = builtins_from_file(source_path)
@@ -226,7 +272,10 @@ def main(source_path: str, output_path: str):
     builtins = each_musique_name_occurs_once(builtins)
     builtins = sorted(list(builtins), key=lambda builtin: builtin.names[0])
 
-    generate_html_document(builtins, output_path)
+    if format == "md":
+        generate_html_document(builtins, output_path)
+    else:
+        generate_cpp_documentation(builtins, output_path)
 
 
 if __name__ == "__main__":
@@ -247,10 +296,21 @@ if __name__ == "__main__":
         required=True,
         help="path for standalone HTML file containing generated documentation",
     )
+    parser.add_argument(
+        "-f",
+        "--format",
+        type=str,
+        default="md",
+        help="output format. One of {html, cpp} are allowed, where HTML yields standalone docs, and C++ mode yields integrated docs",
+    )
 
     PROGRAM_NAME = parser.prog
     args = parser.parse_args()
     assert len(args.source) == 1
     assert len(args.output) == 1
+    assert args.format in (
+        "html",
+        "cpp",
+    ), "Only C++ and HTML output formats are supported"
 
-    main(source_path=args.source[0], output_path=args.output[0])
+    main(source_path=args.source[0], output_path=args.output[0], format=args.format)