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This documentation is for a development version of IPython. There may be significant differences from the latest stable release.

Module: core.magic

Magic functions for InteractiveShell.

4 Classes

class IPython.core.magic.Bunch
class IPython.core.magic.MagicsManager(shell=None, config=None, user_magics=None, **traits)

Bases: IPython.config.configurable.Configurable

Object that handles all magic-related functionality for IPython.

__init__(shell=None, config=None, user_magics=None, **traits)
auto_status()

Return descriptive string with automagic status.

define_magic(name, func)

[Deprecated] Expose own function as magic function for IPython.

Example:

def foo_impl(self, parameter_s=''):
    'My very own magic!. (Use docstrings, IPython reads them).'
    print 'Magic function. Passed parameter is between < >:'
    print '<%s>' % parameter_s
    print 'The self object is:', self

ip.define_magic('foo',foo_impl)
lsmagic()

Return a dict of currently available magic functions.

The return dict has the keys ‘line’ and ‘cell’, corresponding to the two types of magics we support. Each value is a list of names.

lsmagic_docs(brief=False, missing='')

Return dict of documentation of magic functions.

The return dict has the keys ‘line’ and ‘cell’, corresponding to the two types of magics we support. Each value is a dict keyed by magic name whose value is the function docstring. If a docstring is unavailable, the value of missing is used instead.

If brief is True, only the first line of each docstring will be returned.

register(*magic_objects)

Register one or more instances of Magics.

Take one or more classes or instances of classes that subclass the main core.Magic class, and register them with IPython to use the magic functions they provide. The registration process will then ensure that any methods that have decorated to provide line and/or cell magics will be recognized with the %x/%%x syntax as a line/cell magic respectively.

If classes are given, they will be instantiated with the default constructor. If your classes need a custom constructor, you should instanitate them first and pass the instance.

The provided arguments can be an arbitrary mix of classes and instances.

Parameters:magic_objects : one or more classes or instances
register_alias(alias_name, magic_name, magic_kind='line')

Register an alias to a magic function.

The alias is an instance of MagicAlias, which holds the name and kind of the magic it should call. Binding is done at call time, so if the underlying magic function is changed the alias will call the new function.

Parameters:

alias_name : str

The name of the magic to be registered.

magic_name : str

The name of an existing magic.

magic_kind : str

Kind of magic, one of ‘line’ or ‘cell’

register_function(func, magic_kind='line', magic_name=None)

Expose a standalone function as magic function for IPython.

This will create an IPython magic (line, cell or both) from a standalone function. The functions should have the following signatures:

  • For line magics: def f(line)
  • For cell magics: def f(line, cell)
  • For a function that does both: def f(line, cell=None)

In the latter case, the function will be called with cell==None when invoked as %f, and with cell as a string when invoked as %%f.

Parameters:

func : callable

Function to be registered as a magic.

magic_kind : str

Kind of magic, one of ‘line’, ‘cell’ or ‘line_cell’

magic_name : optional str

If given, the name the magic will have in the IPython namespace. By default, the name of the function itself is used.

class IPython.core.magic.Magics(shell=None, **kwargs)

Bases: IPython.config.configurable.Configurable

Base class for implementing magic functions.

Shell functions which can be reached as %function_name. All magic functions should accept a string, which they can parse for their own needs. This can make some functions easier to type, eg %cd ../ vs. %cd(”../”)

Classes providing magic functions need to subclass this class, and they MUST:

  • Use the method decorators @line_magic and @cell_magic to decorate individual methods as magic functions, AND
  • Use the class decorator @magics_class to ensure that the magic methods are properly registered at the instance level upon instance initialization.

See magic_functions for examples of actual implementation classes.

__init__(shell=None, **kwargs)
arg_err(func)

Print docstring if incorrect arguments were passed

default_option(fn, optstr)

Make an entry in the options_table for fn, with value optstr

format_latex(strng)

Format a string for latex inclusion.

parse_options(arg_str, opt_str, *long_opts, **kw)

Parse options passed to an argument string.

The interface is similar to that of getopt.getopt(), but it returns a Struct with the options as keys and the stripped argument string still as a string.

arg_str is quoted as a true sys.argv vector by using shlex.split. This allows us to easily expand variables, glob files, quote arguments, etc.

Parameters:

arg_str : str

The arguments to parse.

opt_str : str

The options specification.

mode : str, default ‘string’

If given as ‘list’, the argument string is returned as a list (split on whitespace) instead of a string.

list_all : bool, default False

Put all option values in lists. Normally only options appearing more than once are put in a list.

posix : bool, default True

Whether to split the input line in POSIX mode or not, as per the conventions outlined in the shlex module from the standard library.

class IPython.core.magic.MagicAlias(shell, magic_name, magic_kind)

Bases: object

An alias to another magic function.

An alias is determined by its magic name and magic kind. Lookup is done at call time, so if the underlying magic changes the alias will call the new function.

Use the MagicsManager.register_alias() method or the %alias_magic magic function to create and register a new alias.

__init__(shell, magic_name, magic_kind)

6 Functions

IPython.core.magic.on_off(tag)

Return an ON/OFF string for a 1/0 input. Simple utility function.

IPython.core.magic.compress_dhist(dh)

Compress a directory history into a new one with at most 20 entries.

Return a new list made from the first and last 10 elements of dhist after removal of duplicates.

IPython.core.magic.needs_local_scope(func)

Decorator to mark magic functions which need to local scope to run.

IPython.core.magic.magics_class(cls)

Class decorator for all subclasses of the main Magics class.

Any class that subclasses Magics must also apply this decorator, to ensure that all the methods that have been decorated as line/cell magics get correctly registered in the class instance. This is necessary because when method decorators run, the class does not exist yet, so they temporarily store their information into a module global. Application of this class decorator copies that global data to the class instance and clears the global.

Obviously, this mechanism is not thread-safe, which means that the creation of subclasses of Magic should only be done in a single-thread context. Instantiation of the classes has no restrictions. Given that these classes are typically created at IPython startup time and before user application code becomes active, in practice this should not pose any problems.

IPython.core.magic.record_magic(dct, magic_kind, magic_name, func)

Utility function to store a function as a magic of a specific kind.

Parameters:

dct : dict

A dictionary with ‘line’ and ‘cell’ subdicts.

magic_kind : str

Kind of magic to be stored.

magic_name : str

Key to store the magic as.

func : function

Callable object to store.

IPython.core.magic.validate_type(magic_kind)

Ensure that the given magic_kind is valid.

Check that the given magic_kind is one of the accepted spec types (stored in the global magic_spec), raise ValueError otherwise.