constraint syntax

// standard constraint syntax

            NSLayoutConstraint.activate([
                avatar.widthAnchor.constraint(equalToConstant: 40.0),
                avatar.heightAnchor.constraint(equalToConstant: 40.0),

                stack.topAnchor.constraint(equalTo: titleView.topAnchor),
                stack.leadingAnchor.constraint(equalTo: titleView.leadingAnchor),
                stack.trailingAnchor.constraint(lessThanOrEqualTo: titleView.trailingAnchor),
                stack.bottomAnchor.constraint(equalTo: titleView.bottomAnchor),
            ])

            let c = titleView.widthAnchor.constraint(equalToConstant: CGFloat.greatestFiniteMagnitude)
            c.priority = .defaultLow
            c.isActive = true

// or, if you want to use SnapKit

            avatar.snp.makeConstraints { make in
                make.width.height.equalTo(40)
            }
            stack.snp.makeConstraints { make in
                make.top.leading.trailing.bottom.equalToSuperview()
            }
            titleView.snp.makeConstraints { make in
                make.width.equalTo(CGFloat.greatestFiniteMagnitude).priority(.low)
            }