.. _`Extract Lambdas`:

.. _`org.sysess.builtin.extractlambdas`:

Extract Lambdas
```````````````

.. image:: extract.svg
   :width: 48


Extract Lambda functions matching datatype in workflows




Documentation
:::::::::::::

Finds and extracts top level Lambda nodes with matching datatype from provided flow files
(.syx).


Input and output datatypes needs to be specified in configuration. The default value:
'() -> ()' represents the generic (? symbol in the GUI) type that can be any type. Examples of
other datatypes are:
- datasource
- table
- adaf
- figure
- text

List datatype is represented by '[<datatype>]'. For example, if the lambda node takes a list of
tables and returns one figure, the datatype specification should be '[table] -> figure' in the
configuration.

The Lambda node will change its type to reflect the choosen datatype as long as it is a
non-generic function type and can be matched against connected nodes. Datatypes configured
that fail to satisfy the above are simply ignored.


Definition
::::::::::


Input ports
...........

    **Filenames**
        | Type: [datasource]
        | Description: Flow filenames containing Lambdas

Output ports
............

    **Functions**
        | Type: [() -> ()]
        | Description: Lambda functions



Configuration
.............

    **Datatype** (datatype)
        Non-generic datatype to match against lambda functions  in input
    **Strategy for handling extraction issues** (fail_strategy)
        How should the node handle the situation when the extract fails?







Examples
........



Example flows demonstrating this node:

* :download:`LambdaOperations.syx </Examples/Sympathy for Data/Generic/Lambda/LambdaOperations.syx>`






Implementation
..............

.. automodule:: node_lambda
    :noindex:

.. class:: ExtractLambdas
    :noindex: