Typo.

src/LRijkstra.ml

@@ -204,7 +204,7 @@ let is_solid s =
    We represent the star rooted at [s] as a trie. For every state [s], the
    star rooted at [s] is constructed in advance, before the algorithm runs.
    While the algorithm runs, a point in the trie (that is, a sub-trie) tells
-   us where we come form, where we are, and which production(s) we are hoping
+   us where we come from, where we are, and which production(s) we are hoping
    to reduce in the future. *)
 
 module Trie : sig