"""
Indentation maker.
@@TR: this code is unsupported and largely undocumented ...
This version is based directly on code by Robert Kuzelj
<robert_kuzelj@yahoo.com> and uses his directive syntax. Some classes and
attributes have been renamed. Indentation is output via
$self._CHEETAH__indenter.indent() to prevent '_indenter' being looked up on the
searchList and another one being found. The directive syntax will
soon be changed somewhat.
"""
import re
import sys
def indentize(source):
return IndentProcessor().process(source)
class IndentProcessor(object):
"""Preprocess #indent tags."""
LINE_SEP = '\n'
ARGS = "args"
INDENT_DIR = re.compile(r'[ \t]*#indent[ \t]*(?P<args>.*)')
DIRECTIVE = re.compile(r"[ \t]*#")
WS = "ws"
WHITESPACES = re.compile(r"(?P<ws>[ \t]*)")
INC = "++"
DEC = "--"
SET = "="
CHAR = "char"
ON = "on"
OFF = "off"
PUSH = "push"
POP = "pop"
def process(self, _txt):
result = []
for line in _txt.splitlines():
match = self.INDENT_DIR.match(line)
if match:
#is indention directive
args = match.group(self.ARGS).strip()
if args == self.ON:
line = "#silent $self._CHEETAH__indenter.on()"
elif args == self.OFF:
line = "#silent $self._CHEETAH__indenter.off()"
elif args == self.INC:
line = "#silent $self._CHEETAH__indenter.inc()"
elif args == self.DEC:
line = "#silent $self._CHEETAH__indenter.dec()"
elif args.startswith(self.SET):
level = int(args[1:])
line = "#silent $self._CHEETAH__indenter.setLevel(%(level)d)" % {"level":level}
elif args.startswith('chars'):
self.indentChars = eval(args.split('=')[1])
line = "#silent $self._CHEETAH__indenter.setChars(%(level)d)" % {"level":level}
elif args.startswith(self.PUSH):
line = "#silent $self._CHEETAH__indenter.push()"
elif args.startswith(self.POP):
line = "#silent $self._CHEETAH__indenter.pop()"
else:
match = self.DIRECTIVE.match(line)
if not match:
#is not another directive
match = self.WHITESPACES.match(line)
if match:
size = len(match.group("ws").expandtabs(4))
line = ("${self._CHEETAH__indenter.indent(%(size)d)}" % {"size":size}) + line.lstrip()
else:
line = "${self._CHEETAH__indenter.indent(0)}" + line
result.append(line)
return self.LINE_SEP.join(result)
class Indenter(object):
"""
A class that keeps track of the current indentation level.
.indent() returns the appropriate amount of indentation.
"""
On = 1
Level = 0
Chars = ' '
LevelStack = []
def on(self):
self.On = 1
def off(self):
self.On = 0
def inc(self):
self.Level += 1
def dec(self):
"""decrement can only be applied to values greater zero
values below zero don't make any sense at all!"""
if self.Level > 0:
self.Level -= 1
def push(self):
self.LevelStack.append(self.Level)
def pop(self):
"""the levestack can not become -1. any attempt to do so
sets the level to 0!"""
if len(self.LevelStack) > 0:
self.Level = self.LevelStack.pop()
else:
self.Level = 0
def setLevel(self, _level):
"""the leve can't be less than zero. any attempt to do so
sets the level automatically to zero!"""
if _level < 0:
self.Level = 0
else:
self.Level = _level
def setChar(self, _chars):
self.Chars = _chars
def indent(self, _default=0):
if self.On:
return self.Chars * self.Level
return " " * _default
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