50 lines
1.3 KiB
Python
50 lines
1.3 KiB
Python
# Exercise 8
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# 1. cut command
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import re
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import sys
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import itertools
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import argparse
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def convert(field):
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field = list(map(lambda f: int(f), field.split("-")))
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if len(field) == 1:
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return field
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else:
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for i in range(field[0], field[-1]):
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field.append(i)
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return sorted(set(field))
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def parse(fields):
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try:
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fields = list(map(convert, fields.split(",")))
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fields = list(itertools.chain(*fields))
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if 0 in fields:
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print("cut: fields are numbered from 1")
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sys.exit(1)
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return list(map(lambda n: n - 1, fields))
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except Exception:
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print(f"cut: valor de campo inválido: «{fields}»")
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sys.exit(1)
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parser = argparse.ArgumentParser()
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parser.add_argument("stream", default=sys.stdin, nargs="?")
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parser.add_argument("-d", "--delimiter", default=False, type=str)
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parser.add_argument("-f", "--fields", type=str, required=True)
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args = parser.parse_args()
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for line in args.stream:
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line = line.strip()
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if args.delimiter is False:
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print(line)
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else:
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fields = re.compile(f"{args.delimiter}+").split(line)
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res = []
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for col in parse(args.fields):
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if col < len(fields):
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res.append(fields[col])
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print(" ".join(res))
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