clarified signature: more explicit operations;

--- a/src/Pure/library.scala	Wed Jan 15 15:13:39 2025 +0100
+++ b/src/Pure/library.scala	Wed Jan 15 15:49:16 2025 +0100
@@ -147,6 +147,8 @@
   def cat_lines(lines: IterableOnce[String]): String =
     lines.iterator.mkString("\n")
 
+  def make_lines(lines: String*): String = cat_lines(lines)
+
   def split_lines(str: String): List[String] = space_explode('\n', str)
 
   def prefix_lines(prfx: String, str: String): String =

--- a/src/Tools/VSCode/src/component_vscodium.scala	Wed Jan 15 15:13:39 2025 +0100
+++ b/src/Tools/VSCode/src/component_vscodium.scala	Wed Jan 15 15:49:16 2025 +0100
@@ -281,13 +281,13 @@
       progress.echo("Prepare ...")
       Isabelle_System.with_copy_dir(vscode_dir, vscode_dir.orig) {
         progress.bash(
-          List(
+          Library.make_lines(
             "set -e",
             platform_info.environment,
             "./prepare_vscode.sh",
             // enforce binary diff of code.xpm
             "cp vscode/resources/linux/code.png vscode/resources/linux/rpm/code.xpm"
-          ).mkString("\n"), cwd = build_dir, echo = progress.verbose).check
+          ), cwd = build_dir, echo = progress.verbose).check
         Isabelle_System.make_patch(build_dir, vscode_dir.orig.base, vscode_dir.base,
           diff_options = "--exclude=.git --exclude=node_modules")
       }