18 lines
626 B
Python
18 lines
626 B
Python
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class pushback_file(file):
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"""Opens a file using the standard file interface adding the ability
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to pushback or unread some section of the file that was read from the file."""
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def __init__(self, fname, mode='r', bufsize=0):
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file.__init__(self, fname, mode, bufsize)
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self.pushed_back = []
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def next(self):
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if len(self.pushed_back):
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return self.pushed_back.pop()
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else:
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return file.next(self)
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def pushback(self, item):
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"""Put some item (bytes, line, etc.) back on the \"front\" of the file"""
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self.pushed_back.append(item)
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