This python module is similar to awk (pattern scanning and processing language in unix/linux). It scans the input file for lines, split each line to fields. *._nr # AWK NR *._nf # AWK NF *._0r # AWK $0 *._1 # AWK strip($1) *._1r # AWK $1 , raw string *._1i # AWK int($1) *._1f # AWK float($1)
Python, 78 lines
Download
Copy to clipboard1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 | """
Awk like module
Usage:
for al in awk_iter_open("some filename"):
print al._nr # AWK NR
print al._nf # AWK NF
print al._0r # AWK $0
print al._1 # AWK strip($1)
print al._1r # AWK $1 , raw string
print al._1i # AWK int($1)
print al._1f # AWK float($1)
"""
import re
def match(s, pattern):
return re.match(pattern, s)
class AwkLine(object):
def __init__(self, line, linenumber=0, sep = None, *args, **kw):
self.line = line.rstrip()
self.fields = line.split(sep)
self.nr = linenumber
super(AwkLine, self).__init__(*args, **kw)
def __getattr__(self, name):
if name in ["nr,", "_nr", "linenumber"]:
return self.nr
if name in [ "_nf", "_n", "n", "nf"]:
return len(self.fields)
if not name.startswith("_"):
raise AttributeError
if name == "_0":
return self.line.strip()
if name == "_0r":
return self.line
if name.endswith("i"):
return int(self.__getattr__(name[:-1]))
if name.endswith("f"):
return float(self.__getattr__(name[:-1]))
if name.endswith("r"): #1r, 2r, 3r
try:
index = int(name[1:-1])
return self.fields[index-1]
except:
raise AttributeError
else: # 1, 2, 3
try:
index = int(name[1:])
return self.fields[index-1].strip()
except:
raise AttributeError
def awk_iter(thefile, sep = None):
for i, line in enumerate(thefile):
yield AwkLine(line, i, sep)
def awk_iter_open(filename, sep=None):
thefile = open(filename, "rt")
for i, line in enumerate(thefile):
yield AwkLine(line, i, sep)
thefile.close()
#
if __name__ == "__main__":
x = AwkLine("hello, this is a test for int 100 and float 3.3")
print x._nr
print x._nf
print x._0
print x._1
print x._8i
print x._11f
for al in awk_iter_open("awk.py"): # this file itself
print al.nr, al._0r
|
Tags: awk
