example-code-2e/03-dict-set/index.py
2015-04-01 22:48:56 -03:00

26 lines
730 B
Python

# adapted from Alex Martelli's example in "Re-learning Python"
# http://www.aleax.it/Python/accu04_Relearn_Python_alex.pdf
# (slide 41) Ex: lines-by-word file index
# BEGIN INDEX
"""Build an index mapping word -> list of occurrences"""
import sys
import re
WORD_RE = re.compile('\w+')
index = {}
with open(sys.argv[1], encoding='utf-8') as fp:
for line_no, line in enumerate(fp, 1):
for match in WORD_RE.finditer(line):
word = match.group()
column_no = match.start()+1
location = (line_no, column_no)
index.setdefault(word, []).append(location) # <1>
# print in alphabetical order
for word in sorted(index, key=str.upper):
print(word, index[word])
# END INDEX