1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
|
:mod:`readline` --- GNU readline interface
==========================================
.. module:: readline
:platform: Unix
:synopsis: GNU readline support for Python.
.. sectionauthor:: Skip Montanaro <skip@pobox.com>
The :mod:`readline` module defines a number of functions to facilitate
completion and reading/writing of history files from the Python interpreter.
This module can be used directly or via the :mod:`rlcompleter` module. Settings
made using this module affect the behaviour of both the interpreter's
interactive prompt and the prompts offered by the built-in :func:`input`
function.
.. note::
On MacOS X the :mod:`readline` module can be implemented using
the ``libedit`` library instead of GNU readline.
The configuration file for ``libedit`` is different from that
of GNU readline. If you programmatically load configuration strings
you can check for the text "libedit" in :const:`readline.__doc__`
to differentiate between GNU readline and libedit.
The :mod:`readline` module defines the following functions:
.. function:: parse_and_bind(string)
Parse and execute single line of a readline init file.
.. function:: get_line_buffer()
Return the current contents of the line buffer.
.. function:: insert_text(string)
Insert text into the command line.
.. function:: read_init_file([filename])
Parse a readline initialization file. The default filename is the last filename
used.
.. function:: read_history_file([filename])
Load a readline history file. The default filename is :file:`~/.history`.
.. function:: write_history_file([filename])
Save a readline history file. The default filename is :file:`~/.history`.
.. function:: clear_history()
Clear the current history. (Note: this function is not available if the
installed version of GNU readline doesn't support it.)
.. function:: get_history_length()
Return the desired length of the history file. Negative values imply unlimited
history file size.
.. function:: set_history_length(length)
Set the number of lines to save in the history file. :func:`write_history_file`
uses this value to truncate the history file when saving. Negative values imply
unlimited history file size.
.. function:: get_current_history_length()
Return the number of lines currently in the history. (This is different from
:func:`get_history_length`, which returns the maximum number of lines that will
be written to a history file.)
.. function:: get_history_item(index)
Return the current contents of history item at *index*.
.. function:: remove_history_item(pos)
Remove history item specified by its position from the history.
.. function:: replace_history_item(pos, line)
Replace history item specified by its position with the given line.
.. function:: redisplay()
Change what's displayed on the screen to reflect the current contents of the
line buffer.
.. function:: set_startup_hook([function])
Set or remove the startup_hook function. If *function* is specified, it will be
used as the new startup_hook function; if omitted or ``None``, any hook function
already installed is removed. The startup_hook function is called with no
arguments just before readline prints the first prompt.
.. function:: set_pre_input_hook([function])
Set or remove the pre_input_hook function. If *function* is specified, it will
be used as the new pre_input_hook function; if omitted or ``None``, any hook
function already installed is removed. The pre_input_hook function is called
with no arguments after the first prompt has been printed and just before
readline starts reading input characters.
.. function:: set_completer([function])
Set or remove the completer function. If *function* is specified, it will be
used as the new completer function; if omitted or ``None``, any completer
function already installed is removed. The completer function is called as
``function(text, state)``, for *state* in ``0``, ``1``, ``2``, ..., until it
returns a non-string value. It should return the next possible completion
starting with *text*.
.. function:: get_completer()
Get the completer function, or ``None`` if no completer function has been set.
.. function:: get_completion_type()
Get the type of completion being attempted.
.. function:: get_begidx()
Get the beginning index of the readline tab-completion scope.
.. function:: get_endidx()
Get the ending index of the readline tab-completion scope.
.. function:: set_completer_delims(string)
Set the readline word delimiters for tab-completion.
.. function:: get_completer_delims()
Get the readline word delimiters for tab-completion.
.. function:: set_completion_display_matches_hook([function])
Set or remove the completion display function. If *function* is
specified, it will be used as the new completion display function;
if omitted or ``None``, any completion display function already
installed is removed. The completion display function is called as
``function(substitution, [matches], longest_match_length)`` once
each time matches need to be displayed.
.. function:: add_history(line)
Append a line to the history buffer, as if it was the last line typed.
.. seealso::
Module :mod:`rlcompleter`
Completion of Python identifiers at the interactive prompt.
.. _readline-example:
Example
-------
The following example demonstrates how to use the :mod:`readline` module's
history reading and writing functions to automatically load and save a history
file named :file:`.pyhist` from the user's home directory. The code below would
normally be executed automatically during interactive sessions from the user's
:envvar:`PYTHONSTARTUP` file. ::
import os
import readline
histfile = os.path.join(os.path.expanduser("~"), ".pyhist")
try:
readline.read_history_file(histfile)
except IOError:
pass
import atexit
atexit.register(readline.write_history_file, histfile)
del os, histfile
The following example extends the :class:`code.InteractiveConsole` class to
support history save/restore. ::
import code
import readline
import atexit
import os
class HistoryConsole(code.InteractiveConsole):
def __init__(self, locals=None, filename="<console>",
histfile=os.path.expanduser("~/.console-history")):
code.InteractiveConsole.__init__(self, locals, filename)
self.init_history(histfile)
def init_history(self, histfile):
readline.parse_and_bind("tab: complete")
if hasattr(readline, "read_history_file"):
try:
readline.read_history_file(histfile)
except IOError:
pass
atexit.register(self.save_history, histfile)
def save_history(self, histfile):
readline.write_history_file(histfile)
|
