Allow action composition over multiple --bind

# Note + prefix in the second bind expression
  fzf --bind u:up --bind u:+up
  fzf --bind u:up+up

src/options.go

@@ -809,7 +809,11 @@ func parseKeymap(keymap map[int][]action, str string) {
 			default:
 				t := isExecuteAction(specLower)
 				if t == actIgnore {
+					if specIndex == 0 && specLower == "" {
+						actions = append(keymap[key], actions...)
+					} else {
 						errorExit("unknown action: " + spec)
+					}
 				} else {
 					var offset int
 					switch t {

src/options_test.go

@@ -246,6 +246,7 @@ func TestBind(t *testing.T) {
 			"f1:execute(ls {+})+abort+execute(echo {+})+select-all,f2:execute/echo {}, {}, {}/,f3:execute[echo '({})'],f4:execute;less {};,"+
 			"alt-a:execute-Multi@echo (,),[,],/,:,;,%,{}@,alt-b:execute;echo (,),[,],/,:,@,%,{};,"+
 			"x:Execute(foo+bar),X:execute/bar+baz/"+
+			",f1:+top,f1:+top"+
 			",,:abort,::accept,+:execute:++\nfoobar,Y:execute(baz)+up")
 	check(tui.CtrlA, "", actKillLine)
 	check(tui.CtrlB, "", actToggleSort, actUp, actDown)
@@ -253,7 +254,7 @@ func TestBind(t *testing.T) {
 	check(tui.AltZ+',', "", actAbort)
 	check(tui.AltZ+':', "", actAccept)
 	check(tui.AltZ, "", actPageDown)
-	check(tui.F1, "ls {+}", actExecute, actAbort, actExecute)
+	check(tui.F1, "ls {+}", actExecute, actAbort, actExecute, actSelectAll, actTop, actTop)
 	check(tui.F2, "echo {}, {}, {}", actExecute)
 	check(tui.F3, "echo '({})'", actExecute)
 	check(tui.F4, "less {}", actExecute)