how can I declare and have my goal to be a (non-)determ instead of procedure

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mdosnov2016
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how can I declare and have my goal to be a (non-)determ instead of procedure

Unread post by mdosnov2016 » 3 Jan 2018 15:26

Because I have a lot of trouble with some nondeterministic calls from inside my project's goal,
how can I declare and have my goal to be a (non-)determ instead of a procedure, as it is declared
now (and I don't know where it is declared as such)?

If I don't have procedure type on my goal the VP8 compiler gives me a related error:
e504 The expression has type '() nondeterm', which is incompatible with the type '() procedure' main.pro

and with the goal being:

Code: Select all

goal     console::runUtf8(main::testtop).
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Thomas Linder Puls
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Re: how can I declare and have my goal to be a (non-)determ instead of procedure

Unread post by Thomas Linder Puls » 4 Jan 2018 13:07

You cannot. The goal must be a procedure. The typical goal in a console program contains a call to console::runUtf8 (as in your code). And predicate you provide as argument in that call must also be a procedure.

So in your code main::testtop must be a procedure.

This is very natural, because the goal is what the program run and a program does not "fail" or return many times.

I suggest you read and follow the tutorials and write "small" code until you are comfortable with things like procedure, determ, nondeterm, backtracking, fail, succeed, cut, ...
Regards Thomas Linder Puls
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