httk.workflow.runtime_utils
===========================

.. py:module:: httk.workflow.runtime_utils

.. autoapi-nested-parse::

   Safe replacements for small conveniences used by shell runners.



Functions
---------

.. autoapisummary::

   httk.workflow.runtime_utils.evaluate_expression
   httk.workflow.runtime_utils.render_template
   httk.workflow.runtime_utils.compress_files
   httk.workflow.runtime_utils.decompress_files


Module Contents
---------------

.. py:function:: evaluate_expression(expression)

   Evaluate a bounded arithmetic expression without Python ``eval``.

   :param expression: Supply the arithmetic expression to evaluate.
   :return: The evaluated scalar result.
   :raises ValueError: If the expression contains an unsupported element.


.. py:function:: render_template(template_path, output_path, values)

   Render ``string.Template`` placeholders from an explicit mapping.

   :param template_path: Locate the source template.
   :param output_path: Locate the atomically replaced output file.
   :param values: Supply placeholder values.
   :return: The rendered output path.
   :raises KeyError: If the template names a missing value.


.. py:function:: compress_files(paths, *, method = 'bz2', remove_source = False)

   Compress regular files atomically with a stdlib codec.

   :param paths: Locate the regular files to compress.
   :param method: Select ``bz2``, ``gz``, or ``xz`` compression.
   :param remove_source: Remove each source after successful compression.
   :return: The compressed output paths.
   :raises ValueError: If a method or source file is invalid.


.. py:function:: decompress_files(paths, *, remove_source = False)

   Decompress ``.bz2``, ``.gz``, or ``.xz`` files atomically.

   :param paths: Locate the compressed files to decompress.
   :param remove_source: Remove each source after successful decompression.
   :return: The decompressed output paths.
   :raises ValueError: If a source is not a supported regular compressed file.
   :raises FileExistsError: If a decompressed output already exists.