Errors

A failure a user can act on is raised as a HeliaAotError. Each one also inherits the standard-library exception that fits it, so code that already catches ValueError or FileNotFoundError keeps working when it calls the converter directly.

An error may carry a hint: one actionable next step, printed dim under the message when the command line reports the failure. The hint is written where the error is raised rather than on the class, so it is specific to what went wrong and is not listed here.

Error	Also a
ConfigValueError	ValueError
GoldenDataKeyError	KeyError
HeliaAotError	Exception
ModelLoadError	FileNotFoundError
OutputExistsError	FileExistsError
TemplateRenderError	RuntimeError
UnsupportedModelError	ValueError

ConfigValueError

class ConfigValueError(HeliaAotError, ValueError)

A configuration value is invalid for the requested conversion.

Also a ValueError so callers catching the stdlib type keep working.

GoldenDataKeyError

class GoldenDataKeyError(HeliaAotError, KeyError)

A supplied golden-data archive is missing a required tensor key.

Also a KeyError so callers catching the stdlib type keep working.

HeliaAotError

class HeliaAotError(Exception)

Base class for user-facing heliaAOT failures.

Args: message: What went wrong, phrased for the user. hint: One actionable next step (rendered dim below the error). details: Supporting output (e.g. tool stderr), rendered dim.

ModelLoadError

class ModelLoadError(HeliaAotError, FileNotFoundError)

The input model could not be found or parsed.

Also a FileNotFoundError so callers catching the stdlib type keep working.

OutputExistsError

class OutputExistsError(HeliaAotError, FileExistsError)

An output path already exists and --force was not given.

Also a FileExistsError so callers catching the stdlib type keep working.

TemplateRenderError

class TemplateRenderError(HeliaAotError, RuntimeError)

A codegen template referenced context its handler did not supply.

The shared Jinja environment uses StrictUndefined, so an undefined name, a missing attribute, or an out-of-range index raises during emit instead of rendering as the empty string. That is always a heliaAOT defect rather than a user mistake, but it is reachable from a valid model, so the failure is reported with the operator, template, and line that produced it and the original UndefinedError is kept as __cause__. Also a RuntimeError so callers catching the stdlib type keep working.

UnsupportedModelError

class UnsupportedModelError(HeliaAotError, ValueError)

The input model uses a structure or dtype heliaAOT cannot lower.

Raised when a graph is recognized but cannot be compiled, so the message can name the recognized construct and the hint can state the supported form. Also a ValueError so callers catching the stdlib type keep working.