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CLI Reference

PyLog provides a simple command‑line interface to consult files and run goals without entering the interactive REPL.

Usage

pylog [FILES ...] [OPTIONS]

python -m prolog.repl [FILES ...] [OPTIONS]

Options

  • -g GOAL, --goal GOAL
  • Run a query and print results.

  • Write the goal without the ?- prefix and without the trailing .

  • --once

  • Print only the first solution. Default when --all is not given.

  • --all

  • Print all solutions, one per line.

  • --noninteractive

  • Do not start the REPL after running the goal.

  • --trace

  • Enable pretty tracing to stdout during the command‑line run.

Examples

Consult files and start the REPL:

pylog prolog/examples/hanoi.pl

Run a goal and exit after the first solution:

pylog prolog/examples/hanoi.pl -g "hanoi(3,left,right,middle,Moves)" --once --noninteractive

Print all solutions of a pure goal:

pylog -g "member(X,[a,b,c])" --all --noninteractive

Enable tracing while running a goal:

pylog -g "append([1],[2],X)" --once --trace --noninteractive

Notes

  • Multiple files can be listed; they are consulted in order.
  • Use shell quoting for goals that contain spaces or operator characters.
  • The Python module entry point (python -m prolog.repl) supports the same options.

See also

  • Getting Started → REPL
  • Guides → Tracing and Debugging