Inheritance diagram for lsst.pex.config.config.Field:

Public Member Functions
	__class_getitem__ (cls, tuple[type,...]\|type\|ForwardRef params)

	__init__ (self, doc, dtype=None, default=None, check=None, optional=False, deprecated=None)

	rename (self, instance)

	validate (self, instance)

	freeze (self, instance)

	save (self, outfile, instance)

	toDict (self, instance)

Field[FieldTypeVar]	__get__ (self, None instance, Any owner=None, Any at=None, str label="default")

FieldTypeVar	__get__ (self, Config instance, Any owner=None, Any at=None, str label="default")

	__get__ (self, instance, owner=None, at=None, label="default")

None	__set__ (self, Config instance, FieldTypeVar\|None value, Any at=None, str label="assignment")

	__delete__ (self, instance, at=None, label="deletion")

Public Attributes
	dtype

	doc

	deprecated

	default

	check

	optional

	source

	name

Static Public Attributes
str	name

dict	supportedTypes = {str, bool, float, int, complex}

Protected Member Functions
	_setup (self, doc, dtype, default, check, optional, source, deprecated)

	_validateValue (self, value)

	_collectImports (self, instance, imports)

	_compare (self, instance1, instance2, shortcut, rtol, atol, output)

Static Protected Member Functions
Mapping[str, Any]	_parseTypingArgs (tuple[type,...]\|tuple[str,...] params, Mapping[str, Any] kwds)

Detailed Description

A field in a `~lsst.pex.config.Config` that supports `int`, `float`,
`complex`, `bool`, and `str` data types.

Parameters
----------
doc : `str`
    A description of the field for users.
dtype : type, optional
    The field's data type. ``Field`` only supports basic data types:
    `int`, `float`, `complex`, `bool`, and `str`. See
    `Field.supportedTypes`. Optional if supplied as a typing argument to
    the class.
default : object, optional
    The field's default value.
check : callable, optional
    A callable that is called with the field's value. This callable should
    return `False` if the value is invalid. More complex inter-field
    validation can be written as part of the
    `lsst.pex.config.Config.validate` method.
optional : `bool`, optional
    This sets whether the field is considered optional, and therefore
    doesn't need to be set by the user. When `False`,
    `lsst.pex.config.Config.validate` fails if the field's value is `None`.
deprecated : None or `str`, optional
    A description of why this Field is deprecated, including removal date.
    If not None, the string is appended to the docstring for this Field.

Raises
------
ValueError
    Raised when the ``dtype`` parameter is not one of the supported types
    (see `Field.supportedTypes`).

See Also
--------
ChoiceField
ConfigChoiceField
ConfigDictField
ConfigField
ConfigurableField
DictField
ListField
RangeField
RegistryField

Notes
-----
``Field`` instances (including those of any subclass of ``Field``) are used
as class attributes of `~lsst.pex.config.Config` subclasses (see the
example, below). ``Field`` attributes work like the `property` attributes
of classes that implement custom setters and getters. `Field` attributes
belong to the class, but operate on the instance. Formally speaking,
`Field` attributes are `descriptors
<https://docs.python.org/3/howto/descriptor.html>`_.

When you access a `Field` attribute on a `Config` instance, you don't
get the `Field` instance itself. Instead, you get the value of that field,
which might be a simple type (`int`, `float`, `str`, `bool`) or a custom
container type (like a `lsst.pex.config.List`) depending on the field's
type. See the example, below.

Fields can be annotated with a type similar to other python classes (python
specification `here <https://peps.python.org/pep-0484/#generics>`_ ).
See the name field in the Config example below for an example of this.
Unlike most other uses in python, this has an effect at type checking *and*
runtime. If the type is specified with a class annotation, it will be used
as the value of the ``dtype`` in the ``Field`` and there is no need to
specify it as an argument during instantiation.

There are Some notes on dtype through type annotation syntax. Type
annotation syntax supports supplying the argument as a string of a type
name. i.e. "float", but this cannot be used to resolve circular references.
Type annotation syntax can be used on an identifier in addition to Class
assignment i.e. ``variable: Field[str] = Config.someField`` vs
``someField = Field[str](doc="some doc"). However, this syntax is only
useful for annotating the type of the identifier (i.e. variable in previous
example) and does nothing for assigning the dtype of the ``Field``.

Examples
--------
Instances of ``Field`` should be used as class attributes of
`lsst.pex.config.Config` subclasses:

>>> from lsst.pex.config import Config, Field
>>> class Example(Config):
...     myInt = Field("An integer field.", int, default=0)
...     name = Field[str](doc="A string Field")
...
>>> print(config.myInt)
0
>>> config.myInt = 5
>>> print(config.myInt)
5

Definition at line 298 of file config.py.

Constructor & Destructor Documentation

◆ init()

lsst.pex.config.config.Field.__init__	(	self,
		doc,
		dtype = None,
		default = None,
		check = None,
		optional = False,
		deprecated = None )

Definition at line 461 of file config.py.

    def __init__(self, doc, dtype=None, default=None, check=None, optional=False, deprecated=None):
        if dtype is None:
            raise ValueError(
                "dtype must either be supplied as an argument or as a type argument to the class"
            )
        if dtype not in self.supportedTypes:
            raise ValueError(f"Unsupported Field dtype {_typeStr(dtype)}")
 
        source = getStackFrame()
        self._setup(
            doc=doc,
            dtype=dtype,
            default=default,
            check=check,
            optional=optional,
            source=source,
            deprecated=deprecated,
        )
 

Member Function Documentation

◆ __class_getitem__()

lsst.pex.config.config.Field.__class_getitem__	(		cls,
		tuple[type, ...] \| type \| ForwardRef	params )

Reimplemented in lsst.pex.config.configurableActions._configurableActionStructField.ConfigurableActionStructField, and lsst.pex.config.configChoiceField.ConfigChoiceField.

Definition at line 458 of file config.py.

    def __class_getitem__(cls, params: tuple[type, ...] | type | ForwardRef):
        return _PexConfigGenericAlias(cls, params)
 

◆ delete()

lsst.pex.config.config.Field.__delete__	(	self,
		instance,
		at = None,
		label = "deletion" )

Delete an attribute from a `lsst.pex.config.Config` instance.

Parameters
----------
instance : `lsst.pex.config.Config`
    The config instance that contains this field.
at : `list` of `lsst.pex.config.callStack.StackFrame`
    The call stack (created by
    `lsst.pex.config.callStack.getCallStack`).
label : `str`, optional
    Event label for the history.

Notes
-----
This is invoked by the owning `~lsst.pex.config.Config` object and
should not be called directly.

Definition at line 794 of file config.py.

    def __delete__(self, instance, at=None, label="deletion"):
        """Delete an attribute from a `lsst.pex.config.Config` instance.
 
        Parameters
        ----------
        instance : `lsst.pex.config.Config`
            The config instance that contains this field.
        at : `list` of `lsst.pex.config.callStack.StackFrame`
            The call stack (created by
            `lsst.pex.config.callStack.getCallStack`).
        label : `str`, optional
            Event label for the history.
 
        Notes
        -----
        This is invoked by the owning `~lsst.pex.config.Config` object and
        should not be called directly.
        """
        if at is None:
            at = getCallStack()
        self.__set__(instance, None, at=at, label=label)
 

◆ get() [1/3]

FieldTypeVar lsst.pex.config.config.Field.__get__	(		self,
		Config	instance,
		Any	owner = None,
		Any	at = None,
		str	label = "default" )

Definition at line 703 of file config.py.

705 ) -> FieldTypeVar: ...

706

◆ get() [2/3]

lsst.pex.config.config.Field.__get__	(	self,
		instance,
		owner = None,
		at = None,
		label = "default" )

Define how attribute access should occur on the Config instance
This is invoked by the owning config object and should not be called
directly.

When the field attribute is accessed on a Config class object, it
returns the field object itself in order to allow inspection of
Config classes.

When the field attribute is access on a config instance, the actual
value described by the field (and held by the Config instance) is
returned.

Definition at line 707 of file config.py.

    def __get__(self, instance, owner=None, at=None, label="default"):
        """Define how attribute access should occur on the Config instance
        This is invoked by the owning config object and should not be called
        directly.
 
        When the field attribute is accessed on a Config class object, it
        returns the field object itself in order to allow inspection of
        Config classes.
 
        When the field attribute is access on a config instance, the actual
        value described by the field (and held by the Config instance) is
        returned.
        """
        if instance is None:
            return self
        else:
            # try statements are almost free in python if they succeed
            try:
                return instance._storage[self.name]
            except AttributeError:
                if not isinstance(instance, Config):
                    return self
                else:
                    raise AttributeError(
                        f"Config {instance} is missing _storage attribute, likely incorrectly initialized"
                    )
 

◆ get() [3/3]

Field[FieldTypeVar] lsst.pex.config.config.Field.__get__	(		self,
		None	instance,
		Any	owner = None,
		Any	at = None,
		str	label = "default" )

Definition at line 698 of file config.py.

700 ) -> Field[FieldTypeVar]: ...

701

◆ set()

None lsst.pex.config.config.Field.__set__	(		self,
		Config	instance,
		FieldTypeVar \| None	value,
		Any	at = None,
		str	label = "assignment" )

Set an attribute on the config instance.

Parameters
----------
instance : `lsst.pex.config.Config`
    The config instance that contains this field.
value : obj
    Value to set on this field.
at : `list` of `~lsst.pex.config.callStack.StackFrame` or `None`,\
        optional
    The call stack (created by
    `lsst.pex.config.callStack.getCallStack`).
label : `str`, optional
    Event label for the history.

Notes
-----
This method is invoked by the owning `lsst.pex.config.Config` object
and should not be called directly.

Derived `~lsst.pex.config.Field` classes may need to override the
behavior. When overriding ``__set__``, `~lsst.pex.config.Field` authors
should follow the following rules:

- Do not allow modification of frozen configs.
- Validate the new value **before** modifying the field. Except if the
  new value is `None`. `None` is special and no attempt should be made
  to validate it until `lsst.pex.config.Config.validate` is called.
- Do not modify the `~lsst.pex.config.Config` instance to contain
  invalid values.
- If the field is modified, update the history of the
  `lsst.pex.config.field.Field` to reflect the changes.

In order to decrease the need to implement this method in derived
`~lsst.pex.config.Field` types, value validation is performed in the
`lsst.pex.config.Field._validateValue`. If only the validation step
differs in the derived `~lsst.pex.config.Field`, it is simpler to
implement `lsst.pex.config.Field._validateValue` than to reimplement
``__set__``. More complicated behavior, however, may require
reimplementation.

Reimplemented in lsst.pex.config.configurableActions._configurableActionField.ConfigurableActionField, lsst.pex.config.configChoiceField.ConfigChoiceField, lsst.pex.config.configField.ConfigField, lsst.pex.config.listField.ListField, lsst.pex.config.dictField.DictField, lsst.pex.config.configurableActions._configurableActionStructField.ConfigurableActionStructField, and lsst.pex.config.configurableField.ConfigurableField.

Definition at line 734 of file config.py.

    ) -> None:
        """Set an attribute on the config instance.
 
        Parameters
        ----------
        instance : `lsst.pex.config.Config`
            The config instance that contains this field.
        value : obj
            Value to set on this field.
        at : `list` of `~lsst.pex.config.callStack.StackFrame` or `None`,\
                optional
            The call stack (created by
            `lsst.pex.config.callStack.getCallStack`).
        label : `str`, optional
            Event label for the history.
 
        Notes
        -----
        This method is invoked by the owning `lsst.pex.config.Config` object
        and should not be called directly.
 
        Derived `~lsst.pex.config.Field` classes may need to override the
        behavior. When overriding ``__set__``, `~lsst.pex.config.Field` authors
        should follow the following rules:
 
        - Do not allow modification of frozen configs.
        - Validate the new value **before** modifying the field. Except if the
          new value is `None`. `None` is special and no attempt should be made
          to validate it until `lsst.pex.config.Config.validate` is called.
        - Do not modify the `~lsst.pex.config.Config` instance to contain
          invalid values.
        - If the field is modified, update the history of the
          `lsst.pex.config.field.Field` to reflect the changes.
 
        In order to decrease the need to implement this method in derived
        `~lsst.pex.config.Field` types, value validation is performed in the
        `lsst.pex.config.Field._validateValue`. If only the validation step
        differs in the derived `~lsst.pex.config.Field`, it is simpler to
        implement `lsst.pex.config.Field._validateValue` than to reimplement
        ``__set__``. More complicated behavior, however, may require
        reimplementation.
        """
        if instance._frozen:
            raise FieldValidationError(self, instance, "Cannot modify a frozen Config")
 
        history = instance._history.setdefault(self.name, [])
        if value is not None:
            value = _autocast(value, self.dtype)
            try:
                self._validateValue(value)
            except BaseException as e:
                raise FieldValidationError(self, instance, str(e))
 
        instance._storage[self.name] = value
        if at is None:
            at = getCallStack()
        history.append((value, at, label))
 

◆ _collectImports()

lsst.pex.config.config.Field._collectImports	(	self,
		instance,
		imports )

protected

Call the _collectImports method on all config
objects the field may own, and union them with the supplied imports
set.

Parameters
----------
instance : instance or subclass of `lsst.pex.config.Config`
    A config object that has this field defined on it
imports : `set`
    Set of python modules that need imported after persistence

Reimplemented in lsst.pex.config.configChoiceField.ConfigChoiceField, lsst.pex.config.configDictField.ConfigDictField, lsst.pex.config.configField.ConfigField, lsst.pex.config.configurableActions._configurableActionStructField.ConfigurableActionStructField, and lsst.pex.config.configurableField.ConfigurableField.

Definition at line 620 of file config.py.

    def _collectImports(self, instance, imports):
        """Call the _collectImports method on all config
        objects the field may own, and union them with the supplied imports
        set.
 
        Parameters
        ----------
        instance : instance or subclass of `lsst.pex.config.Config`
            A config object that has this field defined on it
        imports : `set`
            Set of python modules that need imported after persistence
        """
        pass
 

◆ _compare()

lsst.pex.config.config.Field._compare	(	self,
		instance1,
		instance2,
		shortcut,
		rtol,
		atol,
		output )

protected

Compare a field (named `Field.name`) in two
`~lsst.pex.config.Config` instances for equality.

Parameters
----------
instance1 : `lsst.pex.config.Config`
    Left-hand side `Config` instance to compare.
instance2 : `lsst.pex.config.Config`
    Right-hand side `Config` instance to compare.
shortcut : `bool`, optional
    **Unused.**
rtol : `float`, optional
    Relative tolerance for floating point comparisons.
atol : `float`, optional
    Absolute tolerance for floating point comparisons.
output : callable, optional
    A callable that takes a string, used (possibly repeatedly) to
    report inequalities.

Notes
-----
This method must be overridden by more complex `Field` subclasses.

See Also
--------
lsst.pex.config.compareScalars

Reimplemented in lsst.pex.config.configChoiceField.ConfigChoiceField, lsst.pex.config.configDictField.ConfigDictField, lsst.pex.config.configField.ConfigField, lsst.pex.config.configurableActions._configurableActionStructField.ConfigurableActionStructField, lsst.pex.config.configurableField.ConfigurableField, lsst.pex.config.dictField.DictField, and lsst.pex.config.listField.ListField.

Definition at line 816 of file config.py.

    def _compare(self, instance1, instance2, shortcut, rtol, atol, output):
        """Compare a field (named `Field.name`) in two
        `~lsst.pex.config.Config` instances for equality.
 
        Parameters
        ----------
        instance1 : `lsst.pex.config.Config`
            Left-hand side `Config` instance to compare.
        instance2 : `lsst.pex.config.Config`
            Right-hand side `Config` instance to compare.
        shortcut : `bool`, optional
            **Unused.**
        rtol : `float`, optional
            Relative tolerance for floating point comparisons.
        atol : `float`, optional
            Absolute tolerance for floating point comparisons.
        output : callable, optional
            A callable that takes a string, used (possibly repeatedly) to
            report inequalities.
 
        Notes
        -----
        This method must be overridden by more complex `Field` subclasses.
 
        See Also
        --------
        lsst.pex.config.compareScalars
        """
        v1 = getattr(instance1, self.name)
        v2 = getattr(instance2, self.name)
        name = getComparisonName(
            _joinNamePath(instance1._name, self.name), _joinNamePath(instance2._name, self.name)
        )
        return compareScalars(name, v1, v2, dtype=self.dtype, rtol=rtol, atol=atol, output=output)
 
 

◆ _parseTypingArgs()

Mapping[str, Any] lsst.pex.config.config.Field._parseTypingArgs	(	tuple[type, ...] \| tuple[str, ...]	params,
		Mapping[str, Any]	kwds )

staticprotected

Parse type annotations into keyword constructor arguments.

This is a special private method that interprets type arguments (i.e.
Field[str]) into keyword arguments to be passed on to the constructor.

Subclasses of Field can implement this method to customize how they
handle turning type parameters into keyword arguments (see DictField
for an example)

Parameters
----------
params : `tuple` of `type` or `tuple` of str
    Parameters passed to the type annotation. These will either be
    types or strings. Strings are to interpreted as forward references
    and will be treated as such.
kwds : `MutableMapping` with keys of `str` and values of `Any`
    These are the user supplied keywords that are to be passed to the
    Field constructor.

Returns
-------
kwds : `MutableMapping` with keys of `str` and values of `Any`
    The mapping of keywords that will be passed onto the constructor
    of the Field. Should be filled in with any information gleaned
    from the input parameters.

Raises
------
ValueError
    Raised if params is of incorrect length.
    Raised if a forward reference could not be resolved
    Raised if there is a conflict between params and values in kwds

Reimplemented in lsst.pex.config.configurableField.ConfigurableField, and lsst.pex.config.dictField.DictField.

Definition at line 404 of file config.py.

    ) -> Mapping[str, Any]:
        """Parse type annotations into keyword constructor arguments.
 
        This is a special private method that interprets type arguments (i.e.
        Field[str]) into keyword arguments to be passed on to the constructor.
 
        Subclasses of Field can implement this method to customize how they
        handle turning type parameters into keyword arguments (see DictField
        for an example)
 
        Parameters
        ----------
        params : `tuple` of `type` or `tuple` of str
            Parameters passed to the type annotation. These will either be
            types or strings. Strings are to interpreted as forward references
            and will be treated as such.
        kwds : `MutableMapping` with keys of `str` and values of `Any`
            These are the user supplied keywords that are to be passed to the
            Field constructor.
 
        Returns
        -------
        kwds : `MutableMapping` with keys of `str` and values of `Any`
            The mapping of keywords that will be passed onto the constructor
            of the Field. Should be filled in with any information gleaned
            from the input parameters.
 
        Raises
        ------
        ValueError
            Raised if params is of incorrect length.
            Raised if a forward reference could not be resolved
            Raised if there is a conflict between params and values in kwds
        """
        if len(params) > 1:
            raise ValueError("Only single type parameters are supported")
        unpackedParams = params[0]
        if isinstance(unpackedParams, str):
            _typ = ForwardRef(unpackedParams)
            # type ignore below because typeshed seems to be wrong. It
            # indicates there are only 2 args, as it was in python 3.8, but
            # 3.9+ takes 3 args.
            result = _typ._evaluate(globals(), locals(), recursive_guard=set())  # type: ignore
            if result is None:
                raise ValueError("Could not deduce type from input")
            unpackedParams = cast(type, result)
        if "dtype" in kwds and kwds["dtype"] != unpackedParams:
            raise ValueError("Conflicting definition for dtype")
        elif "dtype" not in kwds:
            kwds = {**kwds, **{"dtype": unpackedParams}}
        return kwds
 

◆ _setup()

lsst.pex.config.config.Field._setup	(	self,
		doc,
		dtype,
		default,
		check,
		optional,
		source,
		deprecated )

protected

Set attributes, usually during initialization.

Definition at line 480 of file config.py.

    def _setup(self, doc, dtype, default, check, optional, source, deprecated):
        """Set attributes, usually during initialization."""
        self.dtype = dtype
        """Data type for the field.
        """
 
        if not doc:
            raise ValueError("Docstring is empty.")
 
        # append the deprecation message to the docstring.
        if deprecated is not None:
            doc = f"{doc} Deprecated: {deprecated}"
        self.doc = doc
        """A description of the field (`str`).
        """
 
        self.deprecated = deprecated
        """If not None, a description of why this field is deprecated (`str`).
        """
 
        self.__doc__ = f"{doc} (`{dtype.__name__}`"
        if optional or default is not None:
            self.__doc__ += f", default ``{default!r}``"
        self.__doc__ += ")"
 
        self.default = default
        """Default value for this field.
        """
 
        self.check = check
        """A user-defined function that validates the value of the field.
        """
 
        self.optional = optional
        """Flag that determines if the field is required to be set (`bool`).
 
        When `False`, `lsst.pex.config.Config.validate` will fail if the
        field's value is `None`.
        """
 
        self.source = source
        """The stack frame where this field is defined (`list` of
        `~lsst.pex.config.callStack.StackFrame`).
        """
 

◆ _validateValue()

lsst.pex.config.config.Field._validateValue	(		self,
			value )

protected

Validate a value.

Parameters
----------
value : object
    The value being validated.

Raises
------
TypeError
    Raised if the value's type is incompatible with the field's
    ``dtype``.
ValueError
    Raised if the value is rejected by the ``check`` method.

Reimplemented in lsst.pex.config.choiceField.ChoiceField, and lsst.pex.config.rangeField.RangeField.

Definition at line 592 of file config.py.

    def _validateValue(self, value):
        """Validate a value.
 
        Parameters
        ----------
        value : object
            The value being validated.
 
        Raises
        ------
        TypeError
            Raised if the value's type is incompatible with the field's
            ``dtype``.
        ValueError
            Raised if the value is rejected by the ``check`` method.
        """
        if value is None:
            return
 
        if not isinstance(value, self.dtype):
            msg = (
                f"Value {value} is of incorrect type {_typeStr(value)}. Expected type {_typeStr(self.dtype)}"
            )
            raise TypeError(msg)
        if self.check is not None and not self.check(value):
            msg = f"Value {value} is not a valid value"
            raise ValueError(msg)
 

◆ freeze()

lsst.pex.config.config.Field.freeze	(		self,
			instance )

Make this field read-only (for internal use only).

Parameters
----------
instance : `lsst.pex.config.Config`
    The config instance that contains this field.

Notes
-----
Freezing is only relevant for fields that hold subconfigs. Fields which
hold subconfigs should freeze each subconfig.

**Subclasses should implement this method.**

Reimplemented in lsst.pex.config.configChoiceField.ConfigChoiceField, lsst.pex.config.configDictField.ConfigDictField, lsst.pex.config.configField.ConfigField, lsst.pex.config.configurableActions._configurableActionStructField.ConfigurableActionStructField, and lsst.pex.config.configurableField.ConfigurableField.

Definition at line 575 of file config.py.

    def freeze(self, instance):
        """Make this field read-only (for internal use only).
 
        Parameters
        ----------
        instance : `lsst.pex.config.Config`
            The config instance that contains this field.
 
        Notes
        -----
        Freezing is only relevant for fields that hold subconfigs. Fields which
        hold subconfigs should freeze each subconfig.
 
        **Subclasses should implement this method.**
        """
        pass
 

◆ rename()

lsst.pex.config.config.Field.rename	(		self,
			instance )

Rename the field in a `~lsst.pex.config.Config` (for internal use
only).

Parameters
----------
instance : `lsst.pex.config.Config`
    The config instance that contains this field.

Notes
-----
This method is invoked by the `lsst.pex.config.Config` object that
contains this field and should not be called directly.

Renaming is only relevant for `~lsst.pex.config.Field` instances that
hold subconfigs. `~lsst.pex.config.Field`\s that hold subconfigs should
rename each subconfig with the full field name as generated by
`lsst.pex.config.config._joinNamePath`.

Reimplemented in lsst.pex.config.configurableActions._configurableActionStructField.ConfigurableActionStructField, lsst.pex.config.configChoiceField.ConfigChoiceField, lsst.pex.config.configDictField.ConfigDictField, lsst.pex.config.configField.ConfigField, and lsst.pex.config.configurableField.ConfigurableField.

Definition at line 525 of file config.py.

    def rename(self, instance):
        r"""Rename the field in a `~lsst.pex.config.Config` (for internal use
        only).
 
        Parameters
        ----------
        instance : `lsst.pex.config.Config`
            The config instance that contains this field.
 
        Notes
        -----
        This method is invoked by the `lsst.pex.config.Config` object that
        contains this field and should not be called directly.
 
        Renaming is only relevant for `~lsst.pex.config.Field` instances that
        hold subconfigs. `~lsst.pex.config.Field`\s that hold subconfigs should
        rename each subconfig with the full field name as generated by
        `lsst.pex.config.config._joinNamePath`.
        """
        pass
 

◆ save()

lsst.pex.config.config.Field.save	(	self,
		outfile,
		instance )

Save this field to a file (for internal use only).

Parameters
----------
outfile : file-like object
    A writeable field handle.
instance : `~lsst.pex.config.Config`
    The `~lsst.pex.config.Config` instance that contains this field.

Notes
-----
This method is invoked by the `~lsst.pex.config.Config` object that
contains this field and should not be called directly.

The output consists of the documentation string
(`lsst.pex.config.Field.doc`) formatted as a Python comment. The second
line is formatted as an assignment: ``{fullname}={value}``.

This output can be executed with Python.

Reimplemented in lsst.pex.config.configChoiceField.ConfigChoiceField, lsst.pex.config.configDictField.ConfigDictField, lsst.pex.config.configField.ConfigField, lsst.pex.config.configurableActions._configurableActionField.ConfigurableActionField, lsst.pex.config.configurableActions._configurableActionStructField.ConfigurableActionStructField, and lsst.pex.config.configurableField.ConfigurableField.

Definition at line 634 of file config.py.

    def save(self, outfile, instance):
        """Save this field to a file (for internal use only).
 
        Parameters
        ----------
        outfile : file-like object
            A writeable field handle.
        instance : `~lsst.pex.config.Config`
            The `~lsst.pex.config.Config` instance that contains this field.
 
        Notes
        -----
        This method is invoked by the `~lsst.pex.config.Config` object that
        contains this field and should not be called directly.
 
        The output consists of the documentation string
        (`lsst.pex.config.Field.doc`) formatted as a Python comment. The second
        line is formatted as an assignment: ``{fullname}={value}``.
 
        This output can be executed with Python.
        """
        value = self.__get__(instance)
        fullname = _joinNamePath(instance._name, self.name)
 
        if self.deprecated and value == self.default:
            return
 
        # write full documentation string as comment lines
        # (i.e. first character is #)
        doc = "# " + str(self.doc).replace("\n", "\n# ")
        if isinstance(value, float) and not math.isfinite(value):
            # non-finite numbers need special care
            outfile.write(f"{doc}\n{fullname}=float('{value!r}')\n\n")
        else:
            outfile.write(f"{doc}\n{fullname}={value!r}\n\n")
 

◆ toDict()

lsst.pex.config.config.Field.toDict	(		self,
			instance )

Convert the field value so that it can be set as the value of an
item in a `dict` (for internal use only).

Parameters
----------
instance : `~lsst.pex.config.Config`
    The `~lsst.pex.config.Config` that contains this field.

Returns
-------
value : object
    The field's value. See *Notes*.

Notes
-----
This method invoked by the owning `~lsst.pex.config.Config` object and
should not be called directly.

Simple values are passed through. Complex data structures must be
manipulated. For example, a `~lsst.pex.config.Field` holding a
subconfig should, instead of the subconfig object, return a `dict`
where the keys are the field names in the subconfig, and the values are
the field values in the subconfig.

Reimplemented in lsst.pex.config.configChoiceField.ConfigChoiceField, lsst.pex.config.configDictField.ConfigDictField, lsst.pex.config.configField.ConfigField, lsst.pex.config.configurableActions._configurableActionStructField.ConfigurableActionStructField, lsst.pex.config.configurableField.ConfigurableField, lsst.pex.config.dictField.DictField, and lsst.pex.config.listField.ListField.

Definition at line 670 of file config.py.

    def toDict(self, instance):
        """Convert the field value so that it can be set as the value of an
        item in a `dict` (for internal use only).
 
        Parameters
        ----------
        instance : `~lsst.pex.config.Config`
            The `~lsst.pex.config.Config` that contains this field.
 
        Returns
        -------
        value : object
            The field's value. See *Notes*.
 
        Notes
        -----
        This method invoked by the owning `~lsst.pex.config.Config` object and
        should not be called directly.
 
        Simple values are passed through. Complex data structures must be
        manipulated. For example, a `~lsst.pex.config.Field` holding a
        subconfig should, instead of the subconfig object, return a `dict`
        where the keys are the field names in the subconfig, and the values are
        the field values in the subconfig.
        """
        return self.__get__(instance)
 

◆ validate()

lsst.pex.config.config.Field.validate	(		self,
			instance )

Validate the field (for internal use only).

Parameters
----------
instance : `lsst.pex.config.Config`
    The config instance that contains this field.

Raises
------
lsst.pex.config.FieldValidationError
    Raised if verification fails.

Notes
-----
This method provides basic validation:

- Ensures that the value is not `None` if the field is not optional.
- Ensures type correctness.
- Ensures that the user-provided ``check`` function is valid.

Most `~lsst.pex.config.Field` subclasses should call
`lsst.pex.config.Field.validate` if they re-implement
`~lsst.pex.config.Field.validate`.

Reimplemented in lsst.pex.config.configurableActions._configurableActionStructField.ConfigurableActionStructField, lsst.pex.config.configChoiceField.ConfigChoiceField, lsst.pex.config.configDictField.ConfigDictField, lsst.pex.config.configField.ConfigField, lsst.pex.config.configurableField.ConfigurableField, lsst.pex.config.dictField.DictField, and lsst.pex.config.listField.ListField.

Definition at line 546 of file config.py.

    def validate(self, instance):
        """Validate the field (for internal use only).
 
        Parameters
        ----------
        instance : `lsst.pex.config.Config`
            The config instance that contains this field.
 
        Raises
        ------
        lsst.pex.config.FieldValidationError
            Raised if verification fails.
 
        Notes
        -----
        This method provides basic validation:
 
        - Ensures that the value is not `None` if the field is not optional.
        - Ensures type correctness.
        - Ensures that the user-provided ``check`` function is valid.
 
        Most `~lsst.pex.config.Field` subclasses should call
        `lsst.pex.config.Field.validate` if they re-implement
        `~lsst.pex.config.Field.validate`.
        """
        value = self.__get__(instance)
        if not self.optional and value is None:
            raise FieldValidationError(self, instance, "Required value cannot be None")
 

Member Data Documentation

◆ check

lsst.pex.config.config.Field.check

Definition at line 509 of file config.py.

◆ default

lsst.pex.config.config.Field.default

Definition at line 505 of file config.py.

◆ deprecated

lsst.pex.config.config.Field.deprecated

Definition at line 496 of file config.py.

◆ doc

lsst.pex.config.config.Field.doc

Definition at line 492 of file config.py.

◆ dtype

lsst.pex.config.config.Field.dtype

Definition at line 482 of file config.py.

◆ name [1/2]

str lsst.pex.config.config.Field.name

static

Definition at line 394 of file config.py.

◆ name [2/2]

lsst.pex.config.config.Field.name

Definition at line 847 of file config.py.

◆ optional

lsst.pex.config.config.Field.optional

Definition at line 513 of file config.py.

◆ source

lsst.pex.config.config.Field.source

Definition at line 520 of file config.py.

◆ supportedTypes

dict lsst.pex.config.config.Field.supportedTypes = {str, bool, float, int, complex}

static

Definition at line 399 of file config.py.

The documentation for this class was generated from the following file:

/j/snowflake/release/lsstsw/stack/lsst-scipipe-9.0.0/Linux64/pex_config/g2cdde0e794+c2c89b37c4/python/lsst/pex/config/config.py

Public Member Functions

Public Attributes

Static Public Attributes

Protected Member Functions

Static Protected Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ __init__()

Member Function Documentation

◆ __class_getitem__()

◆ __delete__()

◆ __get__() [1/3]

◆ __get__() [2/3]

◆ __get__() [3/3]

◆ __set__()

◆ _collectImports()

◆ _compare()

◆ _parseTypingArgs()

◆ _setup()

◆ _validateValue()

◆ freeze()

◆ rename()

◆ save()

◆ toDict()

◆ validate()

Member Data Documentation

◆ check

◆ default

◆ deprecated

◆ doc

◆ dtype

◆ name [1/2]

◆ name [2/2]

◆ optional

◆ source

◆ supportedTypes

◆ init()

◆ delete()

◆ get() [1/3]

◆ get() [2/3]

◆ get() [3/3]

◆ set()