SWI-Prolog -- assertion/1

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Predicate assertion/1

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Documentation
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  - The SWI-Prolog library
    - library(debug): Print debug messages and test assertions
- Packages

Availability::- use_module(library(debug)).(can be autoloaded)

[det]assertion(:Goal)

Acts similar to C assert() macro. It has no effect if Goal succeeds. If Goal fails or throws an exception, the following steps are taken:

call prolog:assertion_failed/2. If prolog:assertion_failed/2 fails, then:
- If this is an interactive toplevel thread, print a message, the stack-trace, and finally trap the debugger.
- Otherwise, throw error(assertion_error(Reason, G),_) where Reason is one of fail or the exception raised.

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LogicalCaptain said (2016-12-15T17:36:01):

===The links here don't work.

They should go to

http://eu.swi-prolog.org/pldoc/doc_for?object=prolog%3Aassertion_failed/2

instead of

http://eu.swi-prolog.org/pldoc/debug.html#prolog:assertion_failed/2===

(And can the authorization be fixed? I have to log in on every single page, which is NOT FUN because I have to copypaste the openid ULR every time and I get thrown out again after s short interval, 10 minutes or so.)