Staging
v0.5.1
v0.5.1
https://github.com/python/cpython
Revision a13c60b81029eb37ca1d8fbac00f63ca717e4fd3 authored by Vinay Sajip on 03 July 2004, 11:45:53 UTC, committed by Vinay Sajip on 03 July 2004, 11:45:53 UTC
1 parent d9c0a7a
Tip revision: a13c60b81029eb37ca1d8fbac00f63ca717e4fd3 authored by Vinay Sajip on 03 July 2004, 11:45:53 UTC
Moved example section up to just after the section on Logger objects, and changed it to use the new basicConfig() API
Moved example section up to just after the section on Logger objects, and changed it to use the new basicConfig() API
Tip revision: a13c60b
UndoDelegator.py
import sys
import string
from Tkinter import *
from Delegator import Delegator
#$ event <<redo>>
#$ win <Control-y>
#$ unix <Alt-z>
#$ event <<undo>>
#$ win <Control-z>
#$ unix <Control-z>
#$ event <<dump-undo-state>>
#$ win <Control-backslash>
#$ unix <Control-backslash>
class UndoDelegator(Delegator):
max_undo = 1000
def __init__(self):
Delegator.__init__(self)
self.reset_undo()
def setdelegate(self, delegate):
if self.delegate is not None:
self.unbind("<<undo>>")
self.unbind("<<redo>>")
self.unbind("<<dump-undo-state>>")
Delegator.setdelegate(self, delegate)
if delegate is not None:
self.bind("<<undo>>", self.undo_event)
self.bind("<<redo>>", self.redo_event)
self.bind("<<dump-undo-state>>", self.dump_event)
def dump_event(self, event):
from pprint import pprint
pprint(self.undolist[:self.pointer])
print "pointer:", self.pointer,
print "saved:", self.saved,
print "can_merge:", self.can_merge,
print "get_saved():", self.get_saved()
pprint(self.undolist[self.pointer:])
return "break"
def reset_undo(self):
self.was_saved = -1
self.pointer = 0
self.undolist = []
self.undoblock = 0 # or a CommandSequence instance
self.set_saved(1)
def set_saved(self, flag):
if flag:
self.saved = self.pointer
else:
self.saved = -1
self.can_merge = False
self.check_saved()
def get_saved(self):
return self.saved == self.pointer
saved_change_hook = None
def set_saved_change_hook(self, hook):
self.saved_change_hook = hook
was_saved = -1
def check_saved(self):
is_saved = self.get_saved()
if is_saved != self.was_saved:
self.was_saved = is_saved
if self.saved_change_hook:
self.saved_change_hook()
def insert(self, index, chars, tags=None):
self.addcmd(InsertCommand(index, chars, tags))
def delete(self, index1, index2=None):
self.addcmd(DeleteCommand(index1, index2))
# Clients should call undo_block_start() and undo_block_stop()
# around a sequence of editing cmds to be treated as a unit by
# undo & redo. Nested matching calls are OK, and the inner calls
# then act like nops. OK too if no editing cmds, or only one
# editing cmd, is issued in between: if no cmds, the whole
# sequence has no effect; and if only one cmd, that cmd is entered
# directly into the undo list, as if undo_block_xxx hadn't been
# called. The intent of all that is to make this scheme easy
# to use: all the client has to worry about is making sure each
# _start() call is matched by a _stop() call.
def undo_block_start(self):
if self.undoblock == 0:
self.undoblock = CommandSequence()
self.undoblock.bump_depth()
def undo_block_stop(self):
if self.undoblock.bump_depth(-1) == 0:
cmd = self.undoblock
self.undoblock = 0
if len(cmd) > 0:
if len(cmd) == 1:
# no need to wrap a single cmd
cmd = cmd.getcmd(0)
# this blk of cmds, or single cmd, has already
# been done, so don't execute it again
self.addcmd(cmd, 0)
def addcmd(self, cmd, execute=True):
if execute:
cmd.do(self.delegate)
if self.undoblock != 0:
self.undoblock.append(cmd)
return
if self.can_merge and self.pointer > 0:
lastcmd = self.undolist[self.pointer-1]
if lastcmd.merge(cmd):
return
self.undolist[self.pointer:] = [cmd]
if self.saved > self.pointer:
self.saved = -1
self.pointer = self.pointer + 1
if len(self.undolist) > self.max_undo:
##print "truncating undo list"
del self.undolist[0]
self.pointer = self.pointer - 1
if self.saved >= 0:
self.saved = self.saved - 1
self.can_merge = True
self.check_saved()
def undo_event(self, event):
if self.pointer == 0:
self.bell()
return "break"
cmd = self.undolist[self.pointer - 1]
cmd.undo(self.delegate)
self.pointer = self.pointer - 1
self.can_merge = False
self.check_saved()
return "break"
def redo_event(self, event):
if self.pointer >= len(self.undolist):
self.bell()
return "break"
cmd = self.undolist[self.pointer]
cmd.redo(self.delegate)
self.pointer = self.pointer + 1
self.can_merge = False
self.check_saved()
return "break"
class Command:
# Base class for Undoable commands
tags = None
def __init__(self, index1, index2, chars, tags=None):
self.marks_before = {}
self.marks_after = {}
self.index1 = index1
self.index2 = index2
self.chars = chars
if tags:
self.tags = tags
def __repr__(self):
s = self.__class__.__name__
t = (self.index1, self.index2, self.chars, self.tags)
if self.tags is None:
t = t[:-1]
return s + repr(t)
def do(self, text):
pass
def redo(self, text):
pass
def undo(self, text):
pass
def merge(self, cmd):
return 0
def save_marks(self, text):
marks = {}
for name in text.mark_names():
if name != "insert" and name != "current":
marks[name] = text.index(name)
return marks
def set_marks(self, text, marks):
for name, index in marks.items():
text.mark_set(name, index)
class InsertCommand(Command):
# Undoable insert command
def __init__(self, index1, chars, tags=None):
Command.__init__(self, index1, None, chars, tags)
def do(self, text):
self.marks_before = self.save_marks(text)
self.index1 = text.index(self.index1)
if text.compare(self.index1, ">", "end-1c"):
# Insert before the final newline
self.index1 = text.index("end-1c")
text.insert(self.index1, self.chars, self.tags)
self.index2 = text.index("%s+%dc" % (self.index1, len(self.chars)))
self.marks_after = self.save_marks(text)
##sys.__stderr__.write("do: %s\n" % self)
def redo(self, text):
text.mark_set('insert', self.index1)
text.insert(self.index1, self.chars, self.tags)
self.set_marks(text, self.marks_after)
text.see('insert')
##sys.__stderr__.write("redo: %s\n" % self)
def undo(self, text):
text.mark_set('insert', self.index1)
text.delete(self.index1, self.index2)
self.set_marks(text, self.marks_before)
text.see('insert')
##sys.__stderr__.write("undo: %s\n" % self)
def merge(self, cmd):
if self.__class__ is not cmd.__class__:
return False
if self.index2 != cmd.index1:
return False
if self.tags != cmd.tags:
return False
if len(cmd.chars) != 1:
return False
if self.chars and \
self.classify(self.chars[-1]) != self.classify(cmd.chars):
return False
self.index2 = cmd.index2
self.chars = self.chars + cmd.chars
return True
alphanumeric = string.ascii_letters + string.digits + "_"
def classify(self, c):
if c in self.alphanumeric:
return "alphanumeric"
if c == "\n":
return "newline"
return "punctuation"
class DeleteCommand(Command):
# Undoable delete command
def __init__(self, index1, index2=None):
Command.__init__(self, index1, index2, None, None)
def do(self, text):
self.marks_before = self.save_marks(text)
self.index1 = text.index(self.index1)
if self.index2:
self.index2 = text.index(self.index2)
else:
self.index2 = text.index(self.index1 + " +1c")
if text.compare(self.index2, ">", "end-1c"):
# Don't delete the final newline
self.index2 = text.index("end-1c")
self.chars = text.get(self.index1, self.index2)
text.delete(self.index1, self.index2)
self.marks_after = self.save_marks(text)
##sys.__stderr__.write("do: %s\n" % self)
def redo(self, text):
text.mark_set('insert', self.index1)
text.delete(self.index1, self.index2)
self.set_marks(text, self.marks_after)
text.see('insert')
##sys.__stderr__.write("redo: %s\n" % self)
def undo(self, text):
text.mark_set('insert', self.index1)
text.insert(self.index1, self.chars)
self.set_marks(text, self.marks_before)
text.see('insert')
##sys.__stderr__.write("undo: %s\n" % self)
class CommandSequence(Command):
# Wrapper for a sequence of undoable cmds to be undone/redone
# as a unit
def __init__(self):
self.cmds = []
self.depth = 0
def __repr__(self):
s = self.__class__.__name__
strs = []
for cmd in self.cmds:
strs.append(" %r" % (cmd,))
return s + "(\n" + ",\n".join(strs) + "\n)"
def __len__(self):
return len(self.cmds)
def append(self, cmd):
self.cmds.append(cmd)
def getcmd(self, i):
return self.cmds[i]
def redo(self, text):
for cmd in self.cmds:
cmd.redo(text)
def undo(self, text):
cmds = self.cmds[:]
cmds.reverse()
for cmd in cmds:
cmd.undo(text)
def bump_depth(self, incr=1):
self.depth = self.depth + incr
return self.depth
def main():
from Percolator import Percolator
root = Tk()
root.wm_protocol("WM_DELETE_WINDOW", root.quit)
text = Text()
text.pack()
text.focus_set()
p = Percolator(text)
d = UndoDelegator()
p.insertfilter(d)
root.mainloop()
if __name__ == "__main__":
main()
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