XSB Src (SVN)-old

Second step for implementing de facto standard meta_predicate/1 predicate properties.

First step for implementing de facto standard meta_predicate/1 predicate properties.

Fix for deleting any existing stream aliases when closing a stream using close/2 (already fixed for close/1).

Implemented the built-in predicate false/0 (equivalent to fail/0) as found on recent standardization proposals and already available on other Prolog compilers.

Defined the arithmentic function atan/2 (butt-ugly alias atan/2 also recognized).

Defined the arithmentic constant epsilon/0.

Partial fix for deleting any existing stream aliases when closing a stream. This fix restores compatibility with Logtalk 2.41.0 and later versions.

extended the builtin shell:sys_pid from Unix only to Windows.
Fixed incremental deletes by using incr_unmark_uninterned_nr

Added incremental versions of unmark_uninterned_nr.

Changed a warning to an error for invalidating an incomplete table,
and made the message more descriptive.