Method deleteGroup

docs/app/js/sanddance-app.js:12640–12648

(groupIndex)

            });
        }
        deleteGroup(groupIndex) {
            const groups = [
                ...this.state.groups
            ];
            groups.splice(groupIndex, 1);
            this.setState({
                groups
            });
        }
        newExpression(key, clause) {
            const ex = {
                key,