Module diag 

Diagnostics, error types, and verbosity utilities.

Input: none (foundation module used by other public APIs). Output: common errors, verbosity/logging abstractions, and validation helpers. Scenario: import from here when you need unified error handling (crate::diag::CoppError) or solver verbosity control across modules.

Macros

verbosity_log

Emit a formatted verbosity message through the global diagnostics backend.

Enums

ConstraintError

Error type for constraint storage/query operations.

CoppError

The error type for COPP.

PathError

Error type for path construction and path evaluation APIs.

Verbosity

The verbosity level for logging.
The default value is Silent.
Trace > Debug > Summary > Silent.

VerbosityOutput

Output backend used by verbosity logging.

Functions

emit_verbosity_line

Emit one verbosity message using the configured backend.

set_verbosity_log_file

Configure a log file as verbosity output backend.

set_verbosity_output

Set output backend for all verbosity messages.

verbosity_output

Get current output backend for verbosity messages.