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, b: *std.Build) Directory.Options {
        return .{
            .exclude_extensions = b.dupeStrings(opts.exclude_extensions),
            .include_extensions = if (opts.include_extensions) |incs| b.dupeStrings(incs) else null,
        };
    }
}