TODO.txt

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