# Tracing of `Func` and `Lazy` evaluations The function `trace` can be used to trace evaluation of expressions: * `trace(lambda: expr)` returns a tuple consisting of the result of evaluating `expr` and a (printable) trace of all evaluation steps. * The optional boolean parameter `live` can be used to enable "live tracing", where evaluation steps are printed to `stdout` as they happen. * The optional parameter `skip_steps` can be used to suppress selected set of tracing steps. For example, setting `skip_steps = {DefinitionStep}` suppresses function definition steps in the trace. For examples see [Basics](basics.md#examples) and [demo.py](../examples/demo.py).