added Emacs-style cursor movement

CHANGELOG.md

@@ -6,6 +6,8 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to the
 [Haskell Package Versioning Policy](https://pvp.haskell.org/).
 
-## Unreleased
+## [Unreleased]
 
-## 0.1.0.0 - YYYY-MM-DD
+### Added
+
+- added Emacs-style keybindings for cursor movement

README.md

@@ -67,8 +67,8 @@ effects:
 ### Edit Mode
 
 - ESC: Return to display mode.
-- Up/K: Move the cursor up.
-- Down/J: Move the cursor down.
-- Left/H: Move the cursor left.
-- Right/L: Move the cursor right.
+- Up/K/CTRL-P: Move the cursor up.
+- Down/J/CTRL-N: Move the cursor down.
+- Left/H/CTRL-B: Move the cursor left.
+- Right/L/CTRL-F: Move the cursor right.
 - F: Flip the bit under the cursor (1 becomes 0; 0 becomes 1).

src/Hamming/App/Events.hs

@@ -150,21 +150,25 @@ keyBindingsFor m = coreBindings ++ case m of
       , ( UpEvent
         , [ bind KUp
           , bind 'k'
+          , ctrl 'p'
           ]
         )
       , ( DownEvent
         , [ bind KDown
           , bind 'j'
+          , ctrl 'n'
           ]
         )
       , ( LeftEvent
         , [ bind KLeft
           , bind 'h'
+          , ctrl 'b'
           ]
         )
       , ( RightEvent
         , [ bind KRight
           , bind 'l'
+          , ctrl 'f'
           ]
         )
       , ( FlipBitEvent