82 lines
2.5 KiB
Python

"""
Module implementing message related functions and classes.
"""
from typing import Type, TypeVar
QuestionInst = TypeVar('QuestionInst', bound='Question')
AnswerInst = TypeVar('AnswerInst', bound='Answer')
class MessageError(Exception):
pass
def source_code(text: str, include_delims: bool = False) -> list[str]:
"""
Extract all source code sections from the given text, i. e. all lines
surrounded by lines tarting with '```'. If 'include_delims' is True,
the surrounding lines are included, otherwise they are omitted. The
result list contains every source code section as a single string.
The order in the list represents the order of the sections in the text.
"""
code_sections: list[str] = []
code_lines: list[str] = []
in_code_block = False
for line in text.split('\n'):
if line.strip().startswith('```'):
if include_delims:
code_lines.append(line)
if in_code_block:
code_sections.append('\n'.join(code_lines) + '\n')
code_lines.clear()
in_code_block = not in_code_block
elif in_code_block:
code_lines.append(line)
return code_sections
class Question(str):
"""
A single question with a defined prefix.
"""
prefix = '=== QUESTION ==='
def __new__(cls: Type[QuestionInst], string: str) -> QuestionInst:
"""
Make sure the question string does not contain the prefix.
"""
if cls.prefix in string:
raise MessageError(f"Question '{string}' contains the prefix '{cls.prefix}'")
instance = super().__new__(cls, string)
return instance
def source_code(self, include_delims: bool = False) -> list[str]:
"""
Extract and return all source code sections.
"""
return source_code(self, include_delims)
class Answer(str):
"""
A single answer with a defined prefix.
"""
prefix = '=== ANSWER ==='
def __new__(cls: Type[AnswerInst], string: str) -> AnswerInst:
"""
Make sure the answer string does not contain the prefix.
"""
if cls.prefix in string:
raise MessageError(f"Answer '{string}' contains the prefix '{cls.prefix}'")
instance = super().__new__(cls, string)
return instance
def source_code(self, include_delims: bool = False) -> list[str]:
"""
Extract and return all source code sections.
"""
return source_code(self, include_delims)