Unusual column vector notation with only a left bar to wrap components

Question

I know there are two standard forms to specify an n-dimensional column vector $\mathbf{\vec{v}}$ using square brackets or parentheses: $$\mathbf{\vec{v}} = \begin{bmatrix} v_1 \\ v_2 \\ \vdots \\ v_{n - 1} \\ v_n \end{bmatrix} = \begin{pmatrix} v_1 \\ v_2 \\ \vdots \\ v_{n - 1} \\ v_n \end{pmatrix}$$ But I have seen someone working in maths writing a form of column vector using only a left vertical bar instead of brackets, like so: $$\mathbf{\vec{v}} = \left\lvert \begin{matrix} v_1 \\ v_2 \\ \vdots \\ v_{n - 1} \\ v_n \end{matrix} \right.$$ I tried to search on Internet about this form with no dice. So I wonder what it is called, or if it's actually an incorrect notation.