34 lines
944 B
Python
34 lines
944 B
Python
"""
|
|
.. data:: BEGIN
|
|
|
|
**BEGIN** token marks the entrypoint of graphs, and all extractors will be connected to this node.
|
|
|
|
Without this, it would be impossible for an execution to actually start anything, as it's the marker that tells
|
|
|bonobo| which node to actually call when the execution starts.
|
|
|
|
.. data:: NOT_MODIFIED
|
|
|
|
**NOT_MODIFIED** is a special value you can return or yield from a transformation to tell bonobo to reuse
|
|
the input data as output.
|
|
|
|
As a convention, all loaders should return this, so loaders can be chained.
|
|
|
|
.. data:: EMPTY
|
|
|
|
Shortcut for "empty tuple". It's often much more clear to write (especially in a test) `write(EMPTY)` than
|
|
`write(())`, although strictly equivalent.
|
|
|
|
|
|
"""
|
|
from bonobo.structs.tokens import Token
|
|
from bonobo.util.envelopes import UnchangedEnvelope
|
|
|
|
BEGIN = Token("Begin")
|
|
END = Token("End")
|
|
|
|
NOT_MODIFIED = UnchangedEnvelope()
|
|
|
|
EMPTY = tuple()
|
|
|
|
TICK_PERIOD = 0.2
|