# Copyright 2025 Open Source Robotics Foundation, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
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"""Module for the StringJoinSubstitution substitution."""
from typing import Iterable, List, Text
from ..launch_context import LaunchContext
from ..some_substitutions_type import SomeSubstitutionsType
from ..substitution import Substitution
from ..utilities import perform_substitutions
[docs]
class StringJoinSubstitution(Substitution):
"""
Substitution that joins strings and/or other substitutions.
This takes in a list of string components as substitutions.
The substitutions for each string component are performed and concatenated,
and then all string components are joined with a specified delimiter as seperation.
For example:
.. code-block:: python
StringJoinSubstitution(
[['https', '://'], LaunchConfiguration('subdomain')], 'ros', 'org'],
delimiter='.'
)
If the ``subdomain`` launch configuration was set to ``docs``
and the ``delimiter`` to ``.``, this would result in a string equal to
.. code-block:: python
'https://docs.ros.org'
"""
[docs]
def __init__(
self,
substitutions: Iterable[SomeSubstitutionsType],
delimiter: SomeSubstitutionsType = '',
) -> None:
"""
Create a StringJoinSubstitution.
:param substitutions: the list of string component substitutions to join
:param delimiter: the text inbetween two consecutive components (default no text)
"""
from ..utilities import normalize_to_list_of_substitutions
self.__substitutions = [
normalize_to_list_of_substitutions(string_component_substitutions)
for string_component_substitutions in substitutions
]
self.__delimiter = normalize_to_list_of_substitutions(delimiter)
@property
def substitutions(self) -> List[List[Substitution]]:
"""Getter for substitutions."""
return self.__substitutions
@property
def delimiter(self) -> List[Substitution]:
"""Getter for delimiter."""
return self.__delimiter
def __repr__(self) -> Text:
"""Return a description of this substitution as a string."""
string_components = [
' + '.join([s.describe() for s in component_substitutions])
for component_substitutions in self.substitutions
]
delimiter_component = ' + '.join([d.describe() for d in self.delimiter])
return (
f'StringJoinSubstitution(['
f'{", ".join(string_components)}], delimiter={delimiter_component})'
)