Extend docs on 'letters' function

Author: WoWaster

lamagraph-compiler/src/Lamagraph/Compiler/Utils.hs

@@ -4,6 +4,10 @@ import Relude
 
 import Data.Sequences qualified
 
--- | This function generates words @a@, ..., @z@, @aa@, ..., @az@ and so on.
+{- | This function generates words @a@, ..., @z@, @aa@, ..., @az@ and so on.
+
+Currently used in "Lamagraph.Compiler.Core.MonadDesugar" and "Lamagraph.Compiler.Typechecker.Helper"
+to generate fresh variable names.
+-}
 letters :: [Text]
 letters = [1 ..] >>= flip Data.Sequences.replicateM ['a' .. 'z']