The Prolog binding

The generated SWI-Prolog predicates call a compiled foreign module over the robot core. Facts return through the final argument, records are dicts, and controls take a list of field=value pairs. Absent results are the atom null, distinct from the valid enum name none. Numeric arguments accept arithmetic expressions. A robot is a fold: optional on_start/2 sets memory and on_turn/3 returns its next value.

Install with make install SDK=/opt/clunkyard/sdk. Run with swipl -q -p library=/opt/clunkyard/sdk/bindings/prolog -s bot.pl -g main -t halt. The foreign module loads libclunkyard.so.2; no compiler runs in the robot.

A tiny robot

:- use_module(library(clunkyard)).
main :- run(user).
on_turn(R,State,State) :-
  sensors_nearest(R,Target),
  (Target==null->
    drive_set(R,[throttle=0.75,turn=0.25]),
    me_heading(R,Heading),scanner_set(R,[heading=Heading,arc=40]),
    scanner_last(R,Scan),status_set(R,[text="SEARCH",value=Scan.arc]);
    gun_power_for_flight_time(R,Target.range,1,Power),gun_lead(R,Target,Power,Aim),
    (Aim==null->gun_aim(R,[heading=Target.bearing,pitch=Target.elevation]);gun_aim(R,[heading=Aim.heading,pitch=Aim.pitch])),
    (gun_can_fire(R,Power,10,true)->gun_fire(R,[power=Power]);true),
    me_heading(R,Heading),angles_angle_diff(Target.bearing,Heading,Off),angles_clamp(Off,-1,1,Turn),
    drive_set(R,[throttle=0.5,turn=Turn]),scanner_set(R,[heading=Target.bearing,arc=10]),status_set(R,[text="TRACK",value=Target.range])).

make test SDK=... checks the actual generated API against every core vector, including exact floating-point results and act lines. Core errors raise a language error carrying their status. A core fault during input sends its empty act and continues with the next state. User exceptions are logged and send the controls already set. Use the binding’s forfeit helper to give up a match; play runs protocol lines in memory for tests.

Names

Every entry of the robot API 2.0.0 in Prolog / CHR. names.md has every language side by side.

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