Keep track of attached files

sage.repl.attach.add_attached_file(filename)

Add to the list of attached files

This is a callback to be used from load() after evaluating the attached file the first time.

INPUT:

  • filename – string, the fully qualified file name.

EXAMPLES:

sage: import sage.repl.attach as af
sage: af.reset()
sage: t = tmp_filename(ext='.py')
sage: af.add_attached_file(t)
sage: af.attached_files()
['/.../tmp_....py']
sage: af.detach(t)
sage: af.attached_files()
[]
sage.repl.attach.attach(*files)

Attach a file or files to a running instance of Sage and also load that file.

Note

Attaching files uses the Python inputhook, which will conflict with other inputhook users. This generally includes GUI main loop integrations, for example tkinter. So you can only use tkinter or attach, but not both at the same time.

INPUT:

  • files – a list of filenames (strings) to attach.

OUTPUT:

Each file is read in and added to an internal list of watched files. The meaning of reading in a file depends on the file type:

  • .py files are read in with no preparsing (so, e.g., 2^3 is 2 bit-xor 3);
  • .sage files are preparsed, then the result is read in;
  • .pyx files are not preparsed, but rather are compiled to a
    module m and then from m import * is executed.

The contents of the file are then loaded, which means they are read into the running Sage session. For example, if foo.sage contains x=5, after attaching foo.sage the variable x will be set to 5. Moreover, any time you change foo.sage, before you execute a command, the attached file will be re-read automatically (with no intervention on your part).

See also

load() is the same as attach(), but doesn’t automatically reload a file when it changes.

EXAMPLES:

You attach a file, e.g., foo.sage or foo.py or foo.pyx, to a running Sage session by typing:

sage: attach('foo.sage')  # not tested

Here we test attaching multiple files at once:

sage: sage.repl.attach.reset()
sage: t1 = tmp_filename(ext='.py')
sage: _ = open(t1,'w').write("print('hello world')")
sage: t2 = tmp_filename(ext='.py')
sage: _ = open(t2,'w').write("print('hi there xxx')")
sage: attach(t1, t2)
hello world
hi there xxx
sage: set(attached_files()) == set([t1,t2])
True

See also

  • attached_files() returns a list of all currently attached files.
  • detach() instructs Sage to remove a file from the internal list of watched files.
  • load_attach_path() allows you to get or modify the current search path for loading and attaching files.
sage.repl.attach.attached_files()

Returns a list of all files attached to the current session with attach().

OUTPUT:

The filenames in a sorted list of strings.

EXAMPLES:

sage: sage.repl.attach.reset()
sage: t = tmp_filename(ext='.py')
sage: _ = open(t,'w').write("print('hello world')")
sage: attach(t)
hello world
sage: attached_files()
['/....py']
sage: attached_files() == [t]
True
sage.repl.attach.detach(filename)

Detach a file.

This is the counterpart to attach().

INPUT:

  • filename – a string, or a list of strings, or a tuple of strings.

EXAMPLES:

sage: sage.repl.attach.reset()
sage: t = tmp_filename(ext='.py')
sage: _ = open(t,'w').write("print('hello world')")
sage: attach(t)
hello world
sage: attached_files() == [t]
True
sage: detach(t)
sage: attached_files()
[]

sage: sage.repl.attach.reset(); reset_load_attach_path()
sage: load_attach_path()
['.']
sage: t_dir = tmp_dir()
sage: fullpath = os.path.join(t_dir, 'test.py')
sage: _ = open(fullpath, 'w').write("print(37 * 3)")
sage: load_attach_path(t_dir, replace=True)
sage: attach('test.py')
111
sage: attached_files() == [os.path.normpath(fullpath)]
True
sage: detach('test.py')
sage: attached_files()
[]
sage: attach('test.py')
111
sage: fullpath = os.path.join(t_dir, 'test2.py')
sage: _ = open(fullpath, 'w').write("print(3)")
sage: attach('test2.py')
3
sage: detach(attached_files())
sage: attached_files()
[]
sage.repl.attach.load_attach_mode(load_debug=None, attach_debug=None)

Get or modify the current debug mode for the behavior of load() and attach() on .sage files.

In debug mode, loaded or attached .sage files are preparsed through a file to make their tracebacks more informative. If not in debug mode, then .sage files are preparsed in memory only for performance.

At startup, debug mode is True for attaching and False for loading.

Note

This function should really be deprecated and code executed from memory should raise proper tracebacks.

INPUT:

  • load_debug – boolean or None (default); if not None, then set a new value for the debug mode for loading files.
  • attach_debug – boolean or None (default); same as load_debug, but for attaching files.

OUTPUT:

If all input values are None, returns a tuple giving the current modes for loading and attaching.

EXAMPLES:

sage: load_attach_mode()
(False, True)
sage: load_attach_mode(attach_debug=False)
sage: load_attach_mode()
(False, False)
sage: load_attach_mode(load_debug=True)
sage: load_attach_mode()
(True, False)
sage: load_attach_mode(load_debug=False, attach_debug=True)
sage.repl.attach.load_attach_path(path=None, replace=False)

Get or modify the current search path for load() and attach().

INPUT:

  • path – string or list of strings (default: None); path(s) to append to or replace the current path.
  • replace – boolean (default: False); if path is not None, whether to replace the search path instead of appending to it.

OUTPUT:

None or a reference to the current search paths.

EXAMPLES:

First, we extend the example given in load()’s docstring:

sage: sage.repl.attach.reset(); reset_load_attach_path()
sage: load_attach_path()
['.']
sage: t_dir = tmp_dir()
sage: fullpath = os.path.join(t_dir, 'test.py')
sage: _ = open(fullpath, 'w').write("print(37 * 3)")

We put SAGE_TMP on the attach path for testing (otherwise this will load test.py from the current working directory if that happens to exist):

sage: load_attach_path(SAGE_TMP, replace=True)
sage: attach('test.py')
Traceback (most recent call last):
...
IOError: did not find file 'test.py' to load or attach
sage: load_attach_path(t_dir)
sage: attach('test.py')
111
sage: attached_files() == [fullpath]
True
sage: sage.repl.attach.reset(); reset_load_attach_path()
sage: load_attach_path() == ['.']
True
sage: load_attach_path(SAGE_TMP, replace=True)
sage: load('test.py')
Traceback (most recent call last):
...
IOError: did not find file 'test.py' to load or attach

The function returns a reference to the path list:

sage: reset_load_attach_path(); load_attach_path()
['.']
sage: load_attach_path('/path/to/my/sage/scripts'); load_attach_path()
['.', '/path/to/my/sage/scripts']
sage: load_attach_path(['good', 'bad', 'ugly'], replace=True)
sage: load_attach_path()
['good', 'bad', 'ugly']
sage: p = load_attach_path(); p.pop()
'ugly'
sage: p[0] = 'weird'; load_attach_path()
['weird', 'bad']
sage: reset_load_attach_path(); load_attach_path()
['.']
sage.repl.attach.modified_file_iterator()

Iterate over the changed files

As a side effect the stored time stamps are updated with the actual time stamps. So if you iterate over the attached files in order to reload them and you hit an error then the subsequent files are not marked as read.

Files that are in the process of being saved are excluded.

EXAMPLES:

sage: sage.repl.attach.reset()
sage: t = tmp_filename(ext='.py')
sage: attach(t)
sage: from sage.repl.attach import modified_file_iterator
sage: list(modified_file_iterator())
[]
sage: sleep(1)   # filesystem mtime granularity
sage: _ = open(t, 'w').write('1')
sage: list(modified_file_iterator())
[('/.../tmp_....py', time.struct_time(...))]
sage.repl.attach.reload_attached_files_if_modified()

Reload attached files that have been modified

This is the internal implementation of the attach mechanism.

EXAMPLES:

sage: sage.repl.attach.reset()
sage: from sage.repl.interpreter import get_test_shell
sage: shell = get_test_shell()
sage: tmp = tmp_filename(ext='.py')
sage: _ = open(tmp, 'w').write('a = 2\n')
sage: shell.run_cell('attach({0})'.format(repr(tmp)))
sage: shell.run_cell('a')
2
sage: sleep(1)   # filesystem mtime granularity
sage: _ = open(tmp, 'w').write('a = 3\n')

Note that the doctests are never really at the command prompt where the automatic reload is triggered. So we have to do it manually:

sage: shell.run_cell('from sage.repl.attach import reload_attached_files_if_modified')
sage: shell.run_cell('reload_attached_files_if_modified()')
### reloading attached file tmp_....py modified at ... ###

sage: shell.run_cell('a')
3
sage: shell.run_cell('detach({0})'.format(repr(tmp)))
sage: shell.run_cell('attached_files()')
[]
sage: shell.quit()
sage.repl.attach.reset()

Remove all the attached files from the list of attached files.

EXAMPLES:

sage: sage.repl.attach.reset()
sage: t = tmp_filename(ext='.py')
sage: _ = open(t,'w').write("print('hello world')")
sage: attach(t)
hello world
sage: attached_files() == [t]
True
sage: sage.repl.attach.reset()
sage: attached_files()
[]
sage.repl.attach.reset_load_attach_path()

Resets the current search path for load() and attach().

The default path is '.' plus any paths specified in the environment variable SAGE_LOAD_ATTACH_PATH.

EXAMPLES:

sage: load_attach_path()
['.']
sage: t_dir = tmp_dir()
sage: load_attach_path(t_dir)
sage: t_dir in load_attach_path()
True
sage: reset_load_attach_path(); load_attach_path()
['.']

At startup, Sage adds colon-separated paths in the environment variable SAGE_LOAD_ATTACH_PATH:

sage: reset_load_attach_path(); load_attach_path()
['.']
sage: os.environ['SAGE_LOAD_ATTACH_PATH'] = '/veni/vidi:vici:'
sage: import imp
sage: imp.reload(sage.repl.attach)    # Simulate startup
<module 'sage.repl.attach' from '...'>
sage: load_attach_path()
['.', '/veni/vidi', 'vici']
sage: del os.environ['SAGE_LOAD_ATTACH_PATH']
sage: imp.reload(sage.repl.preparse)    # Simulate startup
<module 'sage.repl.preparse' from '...'>
sage: reset_load_attach_path(); load_attach_path()
['.']