Continuing confusion

[Peter Phelan]

Hello once again.

I do not wish to annoy anyone with these repeated requests but I can't
find sufficient explanation in any of the documents.

I am trying to make a simple read-write program, at first just to read
some term and reproduce it, and then to read some term, try various
preds from exsiting Prolog code, and write the result.  I hope this way
to discover whether and how it will be possible to port the existing
code to Mercury (yes, I have read the provisos).

I have referred to the user guide, language reference, transition guide,
and sample programs, still can't manage it.  Maybe I have missed
something obvious, but this seems to me a weird and complicated way to
do i/o (yes, I understand why it has to be declarative).  Still, I
cannot understand the meaning of types such as:

list(char)::in


and particularly the operator

::

I am also unable to find any reference to the type:

list:list(character)



which is referred to in many of the compiler.

Thanks in anticpation for your patience.

Rgds

Peter