Options

        pub const Options = struct {
            /// File paths that end in any of these suffixes will be excluded from installation.
            exclude_extensions: []const []const u8 = &.{},
            /// Only file paths that end in any of these suffixes will be included in installation.
            /// `null` means that all suffixes will be included.
            /// `exclude_extensions` takes precedence over `include_extensions`.
            include_extensions: ?[]const []const u8 = &.{".h"},

            pub fn dupe(opts: Directory.Options, graph: *const std.Build.Graph) Directory.Options {
                return .{
                    .exclude_extensions = graph.dupeStrings(opts.exclude_extensions),
                    .include_extensions = if (opts.include_extensions) |incs| graph.dupeStrings(incs) else null,
                };
            }
        }