29 lines
533 B
Python
29 lines
533 B
Python
from collections import deque
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class FileContext(object):
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def __init__(self, file_):
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self._file = file_
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self._line = 0
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self._column = 0
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self._column_stack = deque()
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def getc(self):
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c = self._file.read(1)
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if(c == "\n"):
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self._line += 1
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self._column_stack.append(self._column)
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self._column = 0
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else:
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self._column += 1
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return c
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def ungetc(self, c):
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self._file.seek(self._file.tell() - 1, 0)
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if(c == "\n"):
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self._line -= 1
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self._column = self._column_stack.pop()
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else:
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self._column -= 1
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