33 lines
708 B
Python
33 lines
708 B
Python
# 'grep'
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import regexp
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import string
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def grep(expr, filename):
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prog = regexp.compile(expr)
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fp = open(filename, 'r')
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lineno = 0
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while 1:
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line = fp.readline()
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if not line: break
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lineno = lineno + 1
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res = prog.exec(line)
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if res:
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#print res
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start, end = res[0]
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if line[-1:] = '\n': line = line[:-1]
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prefix = string.rjust(`lineno`, 3) + ': '
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print prefix + line
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if 0:
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line = line[:start]
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if '\t' not in line:
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prefix = ' ' * (len(prefix) + start)
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else:
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prefix = ' ' * len(prefix)
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for c in line:
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if c <> '\t': c = ' '
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prefix = prefix + c
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if start = end: prefix = prefix + '\\'
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else: prefix = prefix + '^'*(end-start)
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print prefix
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