Error Checking and Validation

def check(filenames, select=None, ignore=None):
    """
    Generate PEP 257 errors that exist in filenames iterable.
    
    Parameters:
    - filenames: iterable of str, file paths to check
    - select: list of str, error codes to check for (mutually exclusive with ignore)
    - ignore: list of str, error codes to ignore (mutually exclusive with select)
    
    Returns:
    generator: Error objects for each violation found
    
    Raises:
    IllegalConfiguration: if both select and ignore are provided
    """

import pep257

# Check single file
errors = list(pep257.check(['my_module.py']))

# Check multiple files  
errors = list(pep257.check(['module1.py', 'module2.py']))

# Check with specific error codes
errors = list(pep257.check(['my_module.py'], select=['D100', 'D101', 'D102']))

# Check while ignoring specific errors
errors = list(pep257.check(['my_module.py'], ignore=['D203', 'D213']))

class PEP257Checker:
    """
    Checker for PEP 257 docstring compliance.
    
    Implements all error categories:
    - D10x: Missing docstrings
    - D20x: Whitespace issues  
    - D30x: Docstring formatting
    - D40x: Docstring content issues
    """
    
    def check_source(self, source, filename):
        """
        Check source code string for docstring violations.
        
        Parameters:
        - source: str, Python source code to analyze
        - filename: str, filename for error reporting
        
        Returns:
        generator: Error objects for violations found
        """
    
    @property
    def checks(self):
        """
        Get all available check methods.
        
        Returns:
        list: Check methods sorted by terminal priority
        """

from pep257 import PEP257Checker

checker = PEP257Checker()

# Check source code string
source_code = '''
def hello():
    print("Hello, world!")
'''

errors = list(checker.check_source(source_code, 'example.py'))
for error in errors:
    print(f"{error.filename}:{error.line} {error.code}: {error.message}")

class Error:
    """
    Represents a docstring style error.
    
    Attributes:
    - code: str, error code (e.g., 'D100')
    - short_desc: str, brief error description
    - context: str, contextual information template
    - parameters: tuple, parameters for context formatting
    - definition: Definition, code definition where error occurred
    - explanation: str, detailed explanation of the error
    """
    
    # Class attributes for output formatting
    explain = False  # Show detailed explanations
    source = False   # Show source code context
    
    def set_context(self, definition, explanation):
        """
        Set the context for this error.
        
        Parameters:
        - definition: Definition, code definition object
        - explanation: str, detailed explanation
        """
    
    @property
    def filename(self):
        """str: Filename where error occurred."""
    
    @property  
    def line(self):
        """int: Line number where error occurred."""
    
    @property
    def message(self):
        """str: Formatted error message."""
    
    @property
    def lines(self):
        """str: Source code lines with line numbers."""

class ErrorRegistry:
    """Registry for all error types and error groups."""
    
    groups = []  # List of ErrorGroup instances
    
    @classmethod
    def create_group(cls, prefix, name):
        """
        Create a new error group.
        
        Parameters:
        - prefix: str, error code prefix (e.g., 'D1')
        - name: str, descriptive group name
        
        Returns:
        ErrorGroup: New error group instance
        """
    
    @classmethod
    def get_error_codes(cls):
        """
        Get all registered error codes.
        
        Returns:
        generator: All available error codes
        """
    
    @classmethod
    def to_rst(cls):
        """
        Generate RST table of all errors.
        
        Returns:
        str: Formatted RST table
        """

class ErrorGroup:
    """Represents a group of related errors."""
    
    def __init__(self, prefix, name):
        """
        Initialize error group.
        
        Parameters:
        - prefix: str, error code prefix
        - name: str, group name
        """
    
    def create_error(self, error_code, error_desc, error_context=None):
        """
        Create a new error type in this group.
        
        Parameters:
        - error_code: str, unique error code
        - error_desc: str, error description
        - error_context: str, optional context template
        
        Returns:
        type: New Error subclass
        """

# Missing Docstrings
D1xx = ErrorRegistry.create_group('D1', 'Missing Docstrings')
D100 = D1xx.create_error('D100', 'Missing docstring in public module')
D101 = D1xx.create_error('D101', 'Missing docstring in public class')
D102 = D1xx.create_error('D102', 'Missing docstring in public method')
D103 = D1xx.create_error('D103', 'Missing docstring in public function')
D104 = D1xx.create_error('D104', 'Missing docstring in public package')
D105 = D1xx.create_error('D105', 'Missing docstring in magic method')

# Whitespace Issues
D2xx = ErrorRegistry.create_group('D2', 'Whitespace Issues')

# Quote Issues  
D3xx = ErrorRegistry.create_group('D3', 'Quotes Issues')

# Content Issues
D4xx = ErrorRegistry.create_group('D4', 'Docstring Content Issues')

def main():
    """Main entry point for command-line interface."""

def run_pep257():
    """
    Main runner function with configuration parsing.
    
    Returns:
    int: Exit code (0=no violations, 1=violations, 2=invalid options)
    """

conventions = {
    'pep257': set  # Set of error codes for PEP 257 convention
}

def setup_stream_handlers(conf):
    """
    Setup logging stream handlers according to configuration.
    
    Parameters:
    - conf: RunConfiguration, logging configuration
    """