An unusual (and tiny) pic program

[Douglas McIlroy]

For the edification of pic fans, I have posted
a pic program that lays out binary trees from
one-line functional descriptions like this:

        node(leaf,node(leaf,leaf))

The program is a lovely example of the
power of pic macros and blocks, unlike
anything in the tutorial literature.

Get it from www.cs.dartmouth.ed/~doug/tree.pic.
Try it with  groff -p -ms tree.pic.

Doug