  Field theory is an area in physics with a deceptively compact notation.
Although general purpose computer algebra systems, built around generic
list-based data structures, can be used to represent and manipulate
field-theory expressions, this often leads to cumbersome input formats,
unexpected side-effects, or the need for a lot of special-purpose code. This
makes a direct translation of problems from paper to computer and back
needlessly time-consuming and error-prone. A prototype computer algebra system
is presented which features TeX-like input, graph data structures, lists with
Young-tableaux symmetries and a multiple-inheritance property system. The
usefulness of this approach is illustrated with a number of explicit
field-theory problems.
