_load_template() — langchain Function Reference

Source Code

libs/core/langchain_core/prompts/loading.py lines 44–61

def _load_template(var_name: str, config: dict) -> dict:
    """Load template from the path if applicable."""
    # Check if template_path exists in config.
    if f"{var_name}_path" in config:
        # If it does, make sure template variable doesn't also exist.
        if var_name in config:
            msg = f"Both `{var_name}_path` and `{var_name}` cannot be provided."
            raise ValueError(msg)
        # Pop the template path from the config.
        template_path = Path(config.pop(f"{var_name}_path"))
        # Load the template.
        if template_path.suffix == ".txt":
            template = template_path.read_text(encoding="utf-8")
        else:
            raise ValueError
        # Set the template variable to the extracted variable.
        config[var_name] = template
    return config