diff -r 000000000000 -r 5d1c556ff7db bash-completion.sh
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/bash-completion.sh	Fri May 21 20:16:03 2021 +0200
@@ -0,0 +1,42 @@
+# Relational pipes
+# Copyright © 2021 František Kučera (Frantovo.cz, GlobalCode.info)
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, version 3 of the License.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+_relpipe_tr_infertypes_completion() {
+	local w0 w1 w2 w3
+
+	COMPREPLY=()
+	w0=${COMP_WORDS[COMP_CWORD]}
+	w1=${COMP_WORDS[COMP_CWORD-1]}
+	w2=${COMP_WORDS[COMP_CWORD-2]}
+	w3=${COMP_WORDS[COMP_CWORD-3]}
+
+	MODES=(
+		"auto"
+		"metadata"
+		"data"
+	)
+
+	if   [[ "$w1" == "--relation"                      && "x$w0" == "x" ]];    then COMPREPLY=("'.+'")
+	elif [[ "$w1" == "--mode"                                           ]];    then COMPREPLY=($(compgen -W "${MODES[*]}"  -- "$w0"))
+	else
+		OPTIONS=(
+			"--relation"
+			"--mode"
+		)
+		COMPREPLY=($(compgen -W "${OPTIONS[*]}" -- "$w0"))
+	fi
+}
+
+complete -F _relpipe_tr_infertypes_completion relpipe-tr-infertypes