Source code for langchain_core.utils.formatting

"""Utilities for formatting strings."""

from collections.abc import Mapping, Sequence
from string import Formatter
from typing import Any


[docs] class StrictFormatter(Formatter): """Formatter that checks for extra keys."""
[docs] def vformat( self, format_string: str, args: Sequence, kwargs: Mapping[str, Any] ) -> str: """Check that no arguments are provided. Args: format_string: The format string. args: The arguments. kwargs: The keyword arguments. Returns: The formatted string. Raises: ValueError: If any arguments are provided. """ if len(args) > 0: msg = ( "No arguments should be provided, " "everything should be passed as keyword arguments." ) raise ValueError(msg) return super().vformat(format_string, args, kwargs)
[docs] def validate_input_variables( self, format_string: str, input_variables: list[str] ) -> None: """Check that all input variables are used in the format string. Args: format_string: The format string. input_variables: The input variables. Raises: ValueError: If any input variables are not used in the format string. """ dummy_inputs = {input_variable: "foo" for input_variable in input_variables} super().format(format_string, **dummy_inputs)
formatter = StrictFormatter()