ing together large, multi-part diagrams.</font></p>

<p style="margin-top: 1em"><font color="#000000">Blocks are
also a variable-scoping mechanism, like a <i>groff</i>(1)
environment. All variable assignments done inside a block
are undone at the end of it. To get at values within a
block, write a name of the block followed by a dot, followed
by the label you want. For example, we could refer the the
center of the box in the above composite as <b>last []
.Caption</b> or <b>A.Caption</b>.</font></p>

<p styl