cpython/Lib/grep.py

33 lines
708 B
Python

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