The library contains some functions that can be used to evaluate the
arguments of commands with the expression evaluator (cf. 7).
For instance if the command `Xcom` needs a floating point
parameter, it may be useful to be allowed to write

- interpcom -> Xcom a*(b+cos(x))

as well as

- interpcom -> Xcom 2.252

In this case the parameter must be parsed inside the C-function
corresponding to the command `Xcom`, using the appropriate function
of the library (cf. 7).

2009-11-12