Logging

This document is a work in progress - for a full list of logging options, see Conjure Oxide’s --help output.

To stderr

Using --verbose, and the RUST_LOG environment variable, you can control the contents, and formatting of, Conjure Oxide’s stderr output:

• --verbose changes the formatting of the logs for improved readability, including printing source locations and line numbers for log events. It also enables the printing of the log levels INFO and above.

• The RUST_LOG environment variable can be used to customise the log levels that are printed depending on the module . For more information, see: https://docs.rs/env_logger/latest/env_logger/#enabling-logging.

Example: Logging Rule Applications

Different log levels provide different information about the rules applied to the model:

• INFO provides information on the rules that were applied to the model.

• TRACE additionally prints the rules that were attempted and why they were not applicable.

To see TRACE logs in a pretty format (mainly useful for debugging):

$ RUST_LOG=trace conjure-oxide solve --verbose <model>

Or, using cargo:

$ RUST_LOG=trace cargo run -- solve --verbose <model>

Example: Tracing SAT Solver Rules

When working with the SAT solver, you can trace the complete transformation pipeline:

RUST_LOG=TRACE cargo run -- solve --solver sat my_problem.essence --verbose

This will show:

• Integer-to-boolean conversions
• Operation transformations
• Tseytin transformations
• All rules that were tried and applied

For more detailed testing output (including JSON traces and rewritten models), run specific tests:

cargo test <test_name>

This generates .json and .txt files containing rule traces, parsed Essence, solutions, and the rewritten model.