Using temporary scratch states

To create temporary states (called scratch states) for generation sessions, you can use a with block and pass the result of the scratch_state method of the session as the value. This will save the state of the session, allowing us to perform operations within a scratch state. After the with block is done executing, the original state of the session will be automatically restored.

session = ld.session_for_model("model")

color_choices = ld.chain(
  returns={"color": str},
  nodes=[
    "My favorite color is ",
    ld.choice("color", ["red", "green", "blue"])
  ]
)

with session.scratch_state():
  session.inject("I like red. Red is my favorite color. ")
  print(color_choices.call(session)) # => "red"

session.inject("I like blue. Blue is my favorite color. ")
print(color_choices.call(session)) # => "blue"