Improve documentation and modernize type hints

src/rp/cli.py

@@ -1,10 +1,10 @@
-"""CLI entry point for rp — rich print files beautifully."""
+"""CLI entry point for rp."""
 
 from __future__ import annotations
 
 import sys
 from pathlib import Path
-from typing import Annotated, Optional
+from typing import Annotated
 
 import typer
 from rich.console import Console
@@ -22,6 +22,11 @@ app = typer.Typer(
 
 
 def version_callback(value: bool) -> None:
+    """Print version information and exit.
+
+    Args:
+        value: Flag value from typer callback.
+    """
     if value:
         console = Console()
         console.print(f"Rich Print (rp) {__version__}")
@@ -33,11 +38,11 @@ def version_callback(value: bool) -> None:
 @app.command()
 def main(
     file: Annotated[
-        Optional[Path],
+        Path | None,
         typer.Argument(help="File to rich-print. Use '-' or omit to read from stdin."),
     ] = None,
     file_type: Annotated[
-        Optional[str],
+        str | None,
         typer.Option(
             "--type", "-t", help="Force file type (e.g. json, python, markdown)."
         ),
@@ -47,21 +52,21 @@ def main(
         typer.Option("--theme", help="Pygments color theme."),
     ] = "monokai",
     line_numbers: Annotated[
-        Optional[bool],
+        bool | None,
         typer.Option(
             "--line-numbers/--no-line-numbers",
             help="Show line numbers. Default: auto.",
         ),
     ] = None,
     pager: Annotated[
-        Optional[bool],
+        bool | None,
         typer.Option(
             "--pager/--no-pager",
             help="Use pager for output. Default: auto-detect.",
         ),
     ] = None,
     version: Annotated[
-        Optional[bool],
+        bool | None,
         typer.Option(
             "--version",
             "-v",
@@ -71,7 +76,16 @@ def main(
         ),
     ] = None,
 ) -> None:
-    """Rich print files beautifully in your terminal."""
+    """Render a file or stdin input in the terminal.
+
+    Args:
+        file: File to rich-print. Use '-' or omit to read from stdin.
+        file_type: Force file type (e.g. json, python, markdown).
+        theme: Pygments color theme.
+        line_numbers: Show line numbers. Default: auto.
+        pager: Use pager for output. Default: auto-detect.
+        version: Show version and exit.
+    """
     console = Console()
 
     if file is None or str(file) == "-":