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Prompts

Prompt dataclass

Represents a prompt function.

We return a Prompt class instead of a simple function so the template defined in prompt functions can be accessed.

Source code in outlines/prompts.py
@dataclass
class Prompt:
    """Represents a prompt function.

    We return a `Prompt` class instead of a simple function so the
    template defined in prompt functions can be accessed.

    """

    template: jinja2.Template
    signature: Optional[inspect.Signature]

    def __call__(self, *args, **kwargs) -> str:
        """Render and return the template.

        Returns
        -------
        The rendered template as a Python ``str``.

        """
        if self.signature is not None:
            bound_arguments = self.signature.bind(*args, **kwargs)
            bound_arguments.apply_defaults()
            return self.template.render(**bound_arguments.arguments)
        else:
            return self.template.render(**kwargs)

    @classmethod
    def from_str(cls, content: str, filters: Dict[str, Callable] = {}):
        """
        Create an instance of the class from a string.

        Parameters
        ----------
        content : str
            The string content to be converted into a template.

        Returns
        -------
        An instance of the class with the provided content as a template.
        """
        return cls(cls._template_from_str(content, filters), None)

    @classmethod
    def from_file(cls, path: Path, filters: Dict[str, Callable] = {}):
        """
        Create a Prompt instance from a file containing a Jinja template.

        Note: This method does not allow to include and inheritance to reference files
        that are outside the folder or subfolders of the file given to `from_file`.

        Parameters
        ----------
        path : Path
            The path to the file containing the Jinja template.

        Returns
        -------
        Prompt
            An instance of the Prompt class with the template loaded from the file.
        """
        # We don't use a `Signature` here because it seems not feasible to infer one from a Jinja2 environment that is
        # split across multiple files (since e.g. we support features like Jinja2 includes and template inheritance)
        return cls(cls._template_from_file(path, filters), None)

    @classmethod
    def _template_from_str(
        _, content: str, filters: Dict[str, Callable] = {}
    ) -> jinja2.Template:
        # Dedent, and remove extra linebreak
        cleaned_template = inspect.cleandoc(content)

        # Add linebreak if there were any extra linebreaks that
        # `cleandoc` would have removed
        ends_with_linebreak = content.replace(" ", "").endswith("\n\n")
        if ends_with_linebreak:
            cleaned_template += "\n"

        # Remove extra whitespaces, except those that immediately follow a newline symbol.
        # This is necessary to avoid introducing whitespaces after backslash `\` characters
        # used to continue to the next line without linebreak.
        cleaned_template = re.sub(r"(?![\r\n])(\b\s+)", " ", cleaned_template)

        env = create_jinja_env(None, filters)
        env.filters["name"] = get_fn_name
        env.filters["description"] = get_fn_description
        env.filters["source"] = get_fn_source
        env.filters["signature"] = get_fn_signature
        env.filters["schema"] = get_schema
        env.filters["args"] = get_fn_args

        return env.from_string(cleaned_template)

    @classmethod
    def _template_from_file(
        _, path: Path, filters: Dict[str, Callable] = {}
    ) -> jinja2.Template:
        file_directory = os.path.dirname(os.path.abspath(path))
        env = create_jinja_env(jinja2.FileSystemLoader(file_directory), filters)

        return env.get_template(os.path.basename(path))

__call__(*args, **kwargs)

Render and return the template.

Returns:

Type Description
The rendered template as a Python ``str``.
Source code in outlines/prompts.py
def __call__(self, *args, **kwargs) -> str:
    """Render and return the template.

    Returns
    -------
    The rendered template as a Python ``str``.

    """
    if self.signature is not None:
        bound_arguments = self.signature.bind(*args, **kwargs)
        bound_arguments.apply_defaults()
        return self.template.render(**bound_arguments.arguments)
    else:
        return self.template.render(**kwargs)

from_file(path, filters={}) classmethod

Create a Prompt instance from a file containing a Jinja template.

Note: This method does not allow to include and inheritance to reference files that are outside the folder or subfolders of the file given to from_file.

Parameters:

Name Type Description Default
path Path

The path to the file containing the Jinja template.

required

Returns:

Type Description
Prompt

An instance of the Prompt class with the template loaded from the file.

Source code in outlines/prompts.py
@classmethod
def from_file(cls, path: Path, filters: Dict[str, Callable] = {}):
    """
    Create a Prompt instance from a file containing a Jinja template.

    Note: This method does not allow to include and inheritance to reference files
    that are outside the folder or subfolders of the file given to `from_file`.

    Parameters
    ----------
    path : Path
        The path to the file containing the Jinja template.

    Returns
    -------
    Prompt
        An instance of the Prompt class with the template loaded from the file.
    """
    # We don't use a `Signature` here because it seems not feasible to infer one from a Jinja2 environment that is
    # split across multiple files (since e.g. we support features like Jinja2 includes and template inheritance)
    return cls(cls._template_from_file(path, filters), None)

from_str(content, filters={}) classmethod

Create an instance of the class from a string.

Parameters:

Name Type Description Default
content str

The string content to be converted into a template.

required

Returns:

Type Description
An instance of the class with the provided content as a template.
Source code in outlines/prompts.py
@classmethod
def from_str(cls, content: str, filters: Dict[str, Callable] = {}):
    """
    Create an instance of the class from a string.

    Parameters
    ----------
    content : str
        The string content to be converted into a template.

    Returns
    -------
    An instance of the class with the provided content as a template.
    """
    return cls(cls._template_from_str(content, filters), None)

get_fn_args(fn)

Returns the arguments of a function with annotations and default values if provided.

Source code in outlines/prompts.py
def get_fn_args(fn: Callable):
    """Returns the arguments of a function with annotations and default values if provided."""
    if not callable(fn):
        raise TypeError("The `args` filter only applies to callables.")

    arg_str_list = []
    signature = inspect.signature(fn)
    arg_str_list = [str(param) for param in signature.parameters.values()]
    arg_str = ", ".join(arg_str_list)
    return arg_str

get_fn_description(fn)

Returns the first line of a callable's docstring.

Source code in outlines/prompts.py
def get_fn_description(fn: Callable):
    """Returns the first line of a callable's docstring."""
    if not callable(fn):
        raise TypeError("The `description` filter only applies to callables.")

    docstring = inspect.getdoc(fn)
    if docstring is None:
        description = ""
    else:
        description = docstring.split("\n")[0].strip()

    return description

get_fn_name(fn)

Returns the name of a callable.

Source code in outlines/prompts.py
def get_fn_name(fn: Callable):
    """Returns the name of a callable."""
    if not callable(fn):
        raise TypeError("The `name` filter only applies to callables.")

    if not hasattr(fn, "__name__"):
        name = type(fn).__name__
    else:
        name = fn.__name__

    return name

get_fn_signature(fn)

Return the signature of a callable.

Source code in outlines/prompts.py
def get_fn_signature(fn: Callable):
    """Return the signature of a callable."""
    if not callable(fn):
        raise TypeError("The `source` filter only applies to callables.")

    source = textwrap.dedent(inspect.getsource(fn))
    re_search = re.search(re.compile(r"\(([^)]+)\)"), source)
    if re_search is None:
        signature = ""
    else:
        signature = re_search.group(1)

    return signature

get_fn_source(fn)

Return the source code of a callable.

Source code in outlines/prompts.py
def get_fn_source(fn: Callable):
    """Return the source code of a callable."""
    if not callable(fn):
        raise TypeError("The `source` filter only applies to callables.")

    source = textwrap.dedent(inspect.getsource(fn))
    re_search = re.search(re.compile(r"(\bdef\b.*)", re.DOTALL), source)
    if re_search is not None:
        source = re_search.group(0)
    else:
        raise TypeError("Could not read the function's source code")

    return source

get_schema_dict(model)

Return a pretty-printed dictionary

Source code in outlines/prompts.py
@get_schema.register(dict)
def get_schema_dict(model: Dict):
    """Return a pretty-printed dictionary"""
    return json.dumps(model, indent=2)

get_schema_pydantic(model)

Return the schema of a Pydantic model.

Source code in outlines/prompts.py
@get_schema.register(type(pydantic.BaseModel))
def get_schema_pydantic(model: Type[pydantic.BaseModel]):
    """Return the schema of a Pydantic model."""
    if not isinstance(model, type(pydantic.BaseModel)):
        raise TypeError("The `schema` filter only applies to Pydantic models.")

    if hasattr(model, "model_json_schema"):
        def_key = "$defs"
        raw_schema = model.model_json_schema()
    else:  # pragma: no cover
        def_key = "definitions"
        raw_schema = model.schema()

    definitions = raw_schema.get(def_key, None)
    schema = parse_pydantic_schema(raw_schema, definitions)

    return json.dumps(schema, indent=2)

parse_pydantic_schema(raw_schema, definitions)

Parse the output of Basemodel.[schema|model_json_schema]().

This recursively follows the references to other schemas in case of nested models. Other schemas are stored under the "definitions" key in the schema of the top-level model.

Source code in outlines/prompts.py
def parse_pydantic_schema(raw_schema, definitions):
    """Parse the output of `Basemodel.[schema|model_json_schema]()`.

    This recursively follows the references to other schemas in case
    of nested models. Other schemas are stored under the "definitions"
    key in the schema of the top-level model.

    """
    simple_schema = {}
    for name, value in raw_schema["properties"].items():
        if "description" in value:
            simple_schema[name] = value["description"]
        elif "$ref" in value:
            refs = value["$ref"].split("/")
            simple_schema[name] = parse_pydantic_schema(
                definitions[refs[2]], definitions
            )
        else:
            simple_schema[name] = f"<{name}>"

    return simple_schema

prompt(fn=None, filters={})

Decorate a function that contains a prompt template.

This allows to define prompts in the docstring of a function and simplify their manipulation by providing some degree of encapsulation. It uses the render function internally to render templates.

import outlines

@outlines.prompt def build_prompt(question): ... "I have a ${question}" ... prompt = build_prompt("How are you?")

This API can also be helpful in an "agent" context where parts of the prompt are set when the agent is initialized and never modified later. In this situation we can partially apply the prompt function at initialization.

import outlines import functools as ft ... @outlines.prompt ... def solve_task(name: str, objective: str, task: str): ... '''Your name is {{name}}. .. Your overall objective is to {{objective}}. ... Please solve the following task: {{task}} ... ''' ... hal = ft.partial(solve_task, "HAL", "Travel to Jupiter")

Additional Jinja2 filters can be provided as keyword arguments to the decorator.

def reverse(s: str) -> str: ... return s[::-1] ... @outlines.prompt(filters={ 'reverse': reverse }) ... def reverse_prompt(text): ... '''{{ text | reverse }}''' ... prompt = reverse_prompt("Hello") print(prompt) ... "olleH"

Returns:

Type Description
A `Prompt` callable class which will render the template when called.
Source code in outlines/prompts.py
def prompt(
    fn: Optional[Callable] = None,
    filters: Dict[str, Callable] = {},
) -> Callable:
    """Decorate a function that contains a prompt template.

    This allows to define prompts in the docstring of a function and simplify their
    manipulation by providing some degree of encapsulation. It uses the `render`
    function internally to render templates.

    >>> import outlines
    >>>
    >>> @outlines.prompt
    >>> def build_prompt(question):
    ...    "I have a ${question}"
    ...
    >>> prompt = build_prompt("How are you?")

    This API can also be helpful in an "agent" context where parts of the prompt
    are set when the agent is initialized and never modified later. In this situation
    we can partially apply the prompt function at initialization.

    >>> import outlines
    >>> import functools as ft
    ...
    >>> @outlines.prompt
    ... def solve_task(name: str, objective: str, task: str):
    ...     '''Your name is {{name}}.
    ..      Your overall objective is to {{objective}}.
    ...     Please solve the following task: {{task}}
    ...     '''
    ...
    >>> hal = ft.partial(solve_task, "HAL", "Travel to Jupiter")

    Additional Jinja2 filters can be provided as keyword arguments to the decorator.

    >>> def reverse(s: str) -> str:
    ...     return s[::-1]
    ...
    >>> @outlines.prompt(filters={ 'reverse': reverse })
    ... def reverse_prompt(text):
    ...     '''{{ text | reverse }}'''
    ...
    >>> prompt = reverse_prompt("Hello")
    >>> print(prompt)
    ... "olleH"

    Returns
    -------
    A `Prompt` callable class which will render the template when called.

    """
    if fn is None:
        return lambda fn: prompt(fn, cast(Dict[str, Callable], filters))

    signature = inspect.signature(fn)

    # The docstring contains the template that will be rendered to be used
    # as a prompt to the language model.
    docstring = fn.__doc__
    if docstring is None:
        raise TypeError("Could not find a template in the function's docstring.")

    template = Prompt._template_from_str(cast(str, docstring), filters)

    return Prompt(template, signature)