qarp.errors

OpenQARP exception types.

exception qarp.errors.CapabilityError

Bases: ValueError

A declared capability is incompatible with the engine, circuit, or call.

The single exception type for every engine-capability rejection: raised by the Engine template’s validation hooks at build(), run() and batch_run() time (targets, exactness, noise×amplitudes, mid-circuit operations, initial_state support/routing), by engine constructors for self-contradictory configuration, by StructuredQPEPlan.sample(), and by primitives whose own construction detects an unsupported combination.

Also the rejection type of the emit/absorb SDK boundary: an emitter whose declared gate set or EmitterCapabilities cannot represent a command raises it from emit() (via validate(), before any SDK import), with the offending qarpx.Command attached as the exception’s command attribute; an absorber handed the wrong SDK’s object, or a parameter expression outside the single-symbol linear form, raises it too. A missing SDK is ImportError instead — environment, not circuit. Subclasses ValueError so broad except ValueError handlers keep working.