5. Shape checking

The input in read (and to a lesser extent decode) mode is checked for shape correctness if the -check or -c flag is passed to tnc. This is not guaranteed to pick up all shape errors, but is better than nothing.

When in write mode the results of the shape checking may be viewed by passing the -cv flag to tnc. Each expression is associated with its shape by means of the:

( exp_with_shape exp shape ) -> exp

pseudo-construct. Unknown shapes are indicated by ....