Description
While cobbling together a minimal build of ALS Prolog on Windows (using different tooling than documented in the current version of the root-level README.md), using the Spring 2019/3.5.0 release, and after getting such a build working (just alspro_b/alspro), I noticed the conditionalized interval constraint support in e.g., core\alsp_src\generic\gnu_makefile and the corresponding make option, but while searching the source tree also noticed that the mentioned files are missing:
int_net.c
intaux.c
intrv.c
int_cstr.pro
ra_basis.pro
Similarly, intrv.h included from core\alsp_src\port\wam.c is missing.
On searching through the repository, I can find some previous mentions of e.g., removing some files in some old commits as CLP(BNR) support had been "separated out", and there's some similar residual artifacts, e.g., win32\build_dist.sh shows several lines (61-64) that delete some of the Prolog files. Some constraint/CLP documentation has also been commented out in some documentation (e.g., lines 116-138 of current_prolog_flag.md). I have not yet been able to track down a previous version or commit that actually has int_net.c, intaux.c, intrv.c, et al. still in the source tree.
What's the current status of interval constraint/full CLP(BNR) support in ALS Prolog? Can this code be added back in to the source tree to enable these builds? I have no idea if this is relevant to why the code seems not to be in the current ALS Prolog source tree or not, but the "source archive of final BNR Prolog release, V5.0.5, 1999 for Unix platform(s) of that time" has also been open sourced (under an MIT-style license) as of May 1, 2019.