poco

Generate compose files from portable mappings.

poco takes a simple YAML mapping of trigger sequences to replacement text and turns it into a native compose file for a target platform. It is written in Haskell and is currently a work in progress.

Usage

poco [-t|--target TARGET] <input.yaml>

Example input file (see also: example.yaml):

"ae": "ä"
"oe": "ö"
"ue": "ü"
"hug": "🫂"
"..": "…"

Run poco on the bundled example and compare with the expected output:

stack build
stack exec poco-exe -- example.yaml
diff example.dict <(stack exec poco-exe -- example.yaml)
diff example.compose <(stack exec poco-exe -- -t XComp example.yaml)

XCompose output can be validated with libxkbcommon:

xkbcli compile-compose <(stack exec poco-exe -- -t XComp example.yaml)

Targets

TARGET	Output	Status
Cocoa	DefaultKeyBinding.dict for macOS (default)	implemented
XComp	XCompose file for X11	implemented

Cocoa output deliberately mimics the Python tool gen-compose. For example, "hug": "🫂" becomes:

{"§" = {
  "h" = {
    "u" = {
      "g" = ("insertText:", "🫂");
    };
  };
};}

example.dict shows the full gen-compose output for example.yaml. It currently differs from poco -t Cocoa output in sorting.

Notes

• No trigger sequence may be a prefix of another. Both targets reject inputs such as "a" and "ab", but allow shared prefixes such as "abc" and "abd".
• XCompose sequences match keysyms produced by the active keyboard layout. They do not require US key positions, but the layout must provide the expected symbols. Dead keys such as dead_grave do not match grave, and generated Unicode keysyms may differ from the layout's legacy keysyms. See Compose(5), XkbKeycodeToKeysym(3), and the X11 keysym definitions.
• XCompose results contain only strings, without an accompanying keysym. Applications that require a result keysym may fail to handle this input. For single-character results, emitting both, such as "ä" adiaeresis, could improve compatibility. Multi-character results generally have no corresponding single keysym. See Compose(5) for the result syntax and XmbLookupString(3) for the distinction between XLookupChars and XLookupBoth.