jinja2.ext.Extension Class Reference

Inheritance diagram for jinja2.ext.Extension:

Public Member Functions
None	__init_subclass__ (cls)
None	__init__ (self, Environment environment)
"te.Self"	bind (self, Environment environment)
str	preprocess (self, str source, t.Optional[str] name, t.Optional[str] filename=None)
t.Union["TokenStream", t.Iterable["Token"]]	filter_stream (self, "TokenStream" stream)
t.Union[nodes.Node, t.List[nodes.Node]]	parse (self, "Parser" parser)
nodes.ExtensionAttribute	attr (self, str name, t.Optional[int] lineno=None)
nodes.Call	call_method (self, str name, t.Optional[t.List[nodes.Expr]] args=None, t.Optional[t.List[nodes.Keyword]] kwargs=None, t.Optional[nodes.Expr] dyn_args=None, t.Optional[nodes.Expr] dyn_kwargs=None, t.Optional[int] lineno=None)

Public Attributes
	identifier
	environment

Static Public Attributes
t	identifier .ClassVar[str]
t	tags = set()
int	priority = 100

Detailed Description

Extensions can be used to add extra functionality to the Jinja template
system at the parser level.  Custom extensions are bound to an environment
but may not store environment specific data on `self`.  The reason for
this is that an extension can be bound to another environment (for
overlays) by creating a copy and reassigning the `environment` attribute.

As extensions are created by the environment they cannot accept any
arguments for configuration.  One may want to work around that by using
a factory function, but that is not possible as extensions are identified
by their import name.  The correct way to configure the extension is
storing the configuration values on the environment.  Because this way the
environment ends up acting as central configuration storage the
attributes may clash which is why extensions have to ensure that the names
they choose for configuration are not too generic.  ``prefix`` for example
is a terrible name, ``fragment_cache_prefix`` on the other hand is a good
name as includes the name of the extension (fragment cache).

Member Function Documentation

attr()

nodes.ExtensionAttribute jinja2.ext.Extension.attr	(		self,
		str	name,
		t.Optional[int]	lineno = None
	)

Return an attribute node for the current extension.  This is useful
to pass constants on extensions to generated template code.

::

    self.attr('_my_attribute', lineno=lineno)

bind()

"te.Self" jinja2.ext.Extension.bind	(		self,
		Environment	environment
	)

Create a copy of this extension bound to another environment.

call_method()

nodes.Call jinja2.ext.Extension.call_method	(		self,
		str	name,
		t.Optional[t.List[nodes.Expr]]	args = None,
		t.Optional[t.List[nodes.Keyword]]	kwargs = None,
		t.Optional[nodes.Expr]	dyn_args = None,
		t.Optional[nodes.Expr]	dyn_kwargs = None,
		t.Optional[int]	lineno = None
	)

Call a method of the extension.  This is a shortcut for
:meth:`attr` + :class:`jinja2.nodes.Call`.

filter_stream()

t.Union["TokenStream", t.Iterable["Token"]] jinja2.ext.Extension.filter_stream	(		self,
		"TokenStream"	stream
	)

It's passed a :class:`~jinja2.lexer.TokenStream` that can be used
to filter tokens returned.  This method has to return an iterable of
:class:`~jinja2.lexer.Token`\\s, but it doesn't have to return a
:class:`~jinja2.lexer.TokenStream`.

parse()

t.Union[nodes.Node, t.List[nodes.Node]] jinja2.ext.Extension.parse	(		self,
		"Parser"	parser
	)

If any of the :attr:`tags` matched this method is called with the
parser as first argument.  The token the parser stream is pointing at
is the name token that matched.  This method has to return one or a
list of multiple nodes.

Reimplemented in jinja2.ext.InternationalizationExtension, jinja2.ext.ExprStmtExtension, jinja2.ext.LoopControlExtension, and jinja2.ext.DebugExtension.

preprocess()

str jinja2.ext.Extension.preprocess	(		self,
		str	source,
		t.Optional[str]	name,
		t.Optional[str]	filename = None
	)

This method is called before the actual lexing and can be used to
preprocess the source.  The `filename` is optional.  The return value
must be the preprocessed source.

---

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

• docs/help/help-venv/lib/python3.12/site-packages/jinja2/ext.py