TODO.txt

   1 * Arrays/slices
   2
   3 * Arc, concurrency, channels: Some grep-like thing, "rgrep"
   4 * Send, Sync
   5 * External dependencies: regexp crate, add to rgrep
   6
   7 * Shared-memoty concurrency, interior mutability: Concurrent counter
   8 * Drop, unsafe: doubly-linked list