programs: add readline

hosts/common/programs/assorted.nix

@@ -172,6 +172,7 @@ in
       "pulsemixer"
       "python3-repl"
       # "python3.pkgs.eyeD3"  # music tagging
+      "readline"  # for the config
       "ripgrep"  # needed as a user package so that its user-level config file can be installed
       # "rsyslog"  # KEEP THIS HERE if you want persistent logging (TODO: port to systemd, store in /var/log/...)
       "sane-deadlines"

hosts/common/programs/default.nix

@@ -159,6 +159,7 @@
     ./playerctl.nix
     ./qmk-udev-rules.nix
     ./radicale.nix
+    ./readline.nix
     ./rhythmbox.nix
     ./ripgrep.nix
     ./rofi

hosts/common/programs/readline.nix

@@ -0,0 +1,18 @@
+{ ... }:
+{
+  sane.programs.readline = {
+    packageUnwrapped = null;  # this 'program' is a library: we only care to ship the _config_.
+    fs.".inputrc".symlink.text = ''
+      # docs: <https://tiswww.case.edu/php/chet/readline/readline.html>
+
+      set blink-matching-paren on
+      set colored-completion-prefix on
+      set colored-stats on
+      set editing-mode vi
+      set mark-symlinked-directories on
+      # TODO: print completions in reading order, but only after i configure `ls`/`eza` to do the same.
+      # set print-completions-horizontally on
+      set show-all-if-ambiguous on
+    '';
+  };
+}