Is it possible to make a method, which prints a next line of a code?
def print_next_line():
sth
import fxx
print 'XXX'
print_next_line()
file.split('/')
....
>>> 'XXX'
>>> 'file.split('/')'
I was thinking that It could be somewhere in the stack, but I'm not sure because it is next, not previous line.
Straight approach. I use inspect module to determine file and line where print_next_line was called. Later I read the file to find next string. You might want to add some error handling here (what if there is no next line in a file? and so on)
def print_next_line():
def get_line(f, lineno):
with open(f) as fp:
lines = fp.readlines()
return lines[lineno-1]
import inspect
callerframerecord = inspect.stack()[1]
frame = callerframerecord[0]
info = inspect.getframeinfo(frame)
line_ = info.lineno
file_ = info.filename
print get_line(file_, line_ + 1)
print 'XXX'
a = 1
print_next_line()
b = a*2
All you need is a profiling tool or just a debugger.
Use Python's inspect module:
import inspect
def print_next_line():
lineno = inspect.currentframe().f_back.f_lineno
with open(__file__) as f:
print(f.readlines()[lineno].rstrip())
Well you could open() your .py file and iterate to find specific line, then print it.
Related
So guys, i'm tryng to make a password generator but i'm having this trouble:
First, the code i use for tests:
idTest= "TEST"
passwrd= str(random.randint(11, 99))
if not os.path.exists('Senhas.txt'):
txtFileW = open('Senhas.txt', 'w')
txtFileW.writelines(f'{idTest}: {passwrd}\n')
txtFileW.close()
else:
txtFileA = open('Senhas.txt', 'a')
txtFileA.write(f'{idTest}: {passwrd}\n')
txtFileA.close()
print(f'{idTest}: {passwrd}')
Well, what i'm expecting is something like this:
else:
with open('Senhas.txt', 'r+') as opened:
opened.read()
for lines in opened:
if something == idTest:
lines.replace(f'{something}', f'{idTest}')
else:
break
txtFileA = open('Senhas.txt', 'a')
txtFileA.write(f'{idTest}: {passwrd}\n')
txtFileA.close()
print(f'{idTest}: {passwrd}')
I've searched for it but all i've found are ways to separate it in 2 files (for my project it doesn't match) or with "static" strings, that doesn't match for me as well.
You can use the fileinput module to update the file in place.
import fileinput
with fileinput.input(files=('Senhas.txt'), inplace=True) as f:
for line in f:
if (line.startswith(idTest+':'):
print(f'{idTest}: {passwrd}')
else:
print(line)
Can I configure python to have matlab like print, so that when I just have a function
returnObject()
that it simply prints that object without me having to type print around it? I assume this is not easy, but something like if an object does not get bound by some other var it should get printed, so that this would work.
a = 5 #prints nothing
b = getObject() #prints nothing
a #prints 5
b #prints getObject()
getObject() #prints the object
If you use an ipython notebook individual cells work like this. But you can only view one object per cell by typing the objects name. To see multiple objects you'd need to call print, or use lots of cells.
You could write a script to modify the original script based on a set of rules that define what to print, then run the modified script.
A basic script to do this would be:
f = open('main.py', 'r')
p = open('modified.py', 'w')
p.write('def main(): \n')
for line in f:
temp = line
if len(temp) == 1:
temp = 'print(' + line + ')'
p.write('\t' + temp)
p.close()
from modified import main
main()
The script main.py would then look like this:
x = 236
x
output:
236
Idea is as follows: parse AST of Python code, replace every expression with call to print and content of expression as argument and then run the modified version. I'm not sure whether it works with every code, but you might try. Save it as matlab.py and run your code as python3 -m matlab file.py.
#!/usr/bin/env python3
import ast
import os
import sys
class PrintAdder(ast.NodeTransformer):
def add_print(self, node):
print_func = ast.Name("print", ast.Load())
print_call = ast.Call(print_func, [node.value], [])
print_statement = ast.Expr(print_call)
return print_statement
def visit_Expr(self, node):
if isinstance(node.value, ast.Call) and node.value.func.id == 'print':
return node
return self.add_print(node)
def main():
import argparse
parser = argparse.ArgumentParser()
parser.add_argument('infile', type=argparse.FileType(), nargs='?', default='-')
args = parser.parse_args()
with args.infile as infile:
code = infile.read()
file_name = args.infile.name
tree = ast.parse(code, file_name, 'exec')
tree = PrintAdder().visit(tree)
tree = ast.fix_missing_locations(tree)
bytecode = compile(tree, file_name, 'exec')
exec(bytecode)
if __name__ == '__main__':
main()
I want to pass dictionary to user defined functions and I need to do some calculation based on the dictionary values. It is not working for me with functions but works fine without using functions. I am not sure, what is wrong with code. Any help please? No error message.
Input:
"13-07-2016 12:55:46",user,192.168.10.100,192.168.10.20,CONNECT,200,"www.abc.com"
"13-07-2016 12:57:50",user,192.168.10.100,192.168.10.20,CONNECT,200,"www.abc.com"
"13-07-2016 13:00:43",user,192.168.10.100,192.168.10.20,CONNECT,200,"www.abc.com"
"13-07-2016 13:01:45",user,192.168.10.100,192.168.10.20,CONNECT,200,"www.abc.com"
"13-07-2016 13:02:57",user,192.168.10.100,192.168.10.20,CONNECT,200,"www.abc.com"
"13-07-2016 13:04:59",user,192.168.10.100,192.168.10.20,CONNECT,200,"www.abc.com"
"13-07-2016 13:06:51",user,192.168.10.100,192.168.10.20,CONNECT,200,"www.abc.com"
"13-07-2016 13:07:56",user,192.168.10.100,192.168.10.20,CONNECT,200,"www.abc.com"
Code:
file_name = sys.argv[1]
fo = open(file_name, "rb")
def setdict():
dico,i={},0
line = fo.readline()
for line in fo:
date, user, proxy_ip, client_ip, access_method, con, sites = line.split(",")
sites = sites.rstrip('\n')
dico[i]= date, user, proxy_ip, client_ip, access_method, con, sites
return dico
def display(dico):
for k,v in dico.items():
print k,v
A: You should consider to call your functions at the end of the script:
dico = setdict()
display(dico)
Without that, they are declared, but not used.
B: You should also consider a better way to open your file:
with open(file_name, "rb") as f:
lines = f.readlines()
for line in lines:
# Do stuff with your line
This is the best way to open a file in python and to read it line by line.
C: You are using:
line = fo.readline()
# ^ That line is never use after, you will loose all it's datas
for line in fo:
#do stuff on line
I've add a comment to show you that you loose the data from the first line.
D: You are using global variable (you use fo inside setdict() a better way will be to pass it by arguments:
fo = open(file_name, "rb")
def setdict(fo):
dico,i={},0
line = fo.readline()
...
setdict(fo)
Finally, here is how you can rewrite your script :
def setdict(filename):
dico,i={},0
with open(filename, 'r') as f:
for line in f.readlines():
date, user, proxy_ip, client_ip, access_method, con, sites = line.split(",")
sites = sites.rstrip('\n')
dico[i]= date, user, proxy_ip, client_ip, access_method, con, sites
return dico
def display(dico):
for k,v in dico.items():
print k,v
file_name = sys.argv[1]
dico = setdict(filename)
display(dico)
When you write a function in Python using the def keyword, the function is not automatically executed. You are never calling your setdict or display functions, just defining them so they can be called later.
Add this line to the end of your script to actually call the functions you defined:
display(setdict())
or more verbosely
dico = setdict()
display(dico)
I am iterating a .dat file save on a http website using
import urllib2
test_file = urllib2.urlopen('http://~/file.dat')
And then, I have a function which iterates the file
def f(file):
while True:
iter = file.readline()
if iter == "":
break
print iter
If I want to call this function twice without opening the test_file again:
f(test_file)
f(test_file)
then what should I add into the f function?
Update:
Since I am not allowed to change anything outside the function, I finally came up a silly but effective solution:
def f(file):
while True:
iter = file.readline()
if iter == "":
break
print iter
global test_file
test_file = test_file = urllib2.urlopen('http://~/file.dat')
Thanks for the guys who answered my questions!
f.seek(0)
returns you to the start of the file. The argument is the byte position in the file.
So the best thing for you to do is to save the output of your f.read() to a var and then push through via the StringIO.readline() method that will work similarly to f.readline() but within memory.
import urllib2
import StringIO
t_fh = urllib2.urlopen('http://ftp.cs.stanford.edu/pub/sgb/test.dat')
test_data = t_fh.read()
def f(data):
buf = StringIO.StringIO(data)
while True:
line = buf.readline()
if line == "":
break
print line
f(test_data)
#!/usr/bin/env python`
import sys`
import binascii`
import string
sample = "foo.apples"
data_file = open("file1.py","r")
dat_file = open("file2.txt", "w")
for line in data_file:
if sample in line:
dat_file.writelines(line)
dat_file.close()`
When I do this I am able to find the string foo.apples. The problem is foo.apples is present in various lines in the python file. I want those lines which are inside a particular function. I need the lines within this def function.
Example:
def start():
foo.apples(a,b)
foo.apples(c,d) ... so on.
The following program finds defs and will append the sample string to the output file if the indentation remains within the def.
import re
sample = 'foo.apples'
data_file = open("file1.py", "r")
out_file = open("file2.txt", "w")
within_def = False
def_indent = 0
for line in data_file:
def_match = re.match(r'(\s*)def\s+start\s*\(', line) # EDIT: fixed regex
if def_match and not within_def:
within_def = True
def_indent = len(def_match.group(1))
elif within_def and re.match(r'\s{%s}\S' % def_indent, line):
within_def = False
if within_def and sample in line:
out_file.writelines(line)
out_file.close()
data_file.close()
Tested working on an example file1.py.
One, slightly off the beaten path approach to this would be to use the getsource method of the inspect module. Consider the following (theoretical) test1.py file:
class foo(object):
apples = 'granny_smith'
#classmethod
def new_apples(cls):
cls.apples = 'macintosh'
def start():
"""This is a pretty meaningless python function.
Attempts to run it will definitely result in an exception being thrown"""
print foo.apples
foo.apples = 3
[x for x in range(10)]
import bar as foo
Now you want to know about the start code:
import inspect
import test1 #assume it is somewhere that can be imported
print inspect.getsource(test1.start)
Ok, now we have only the source of that function. We can now parse through that:
for line in inspect.getsource(test1.start).splitlines():
if 'foo.apples' in line:
print line
There are some advantages here -- python does all the work of parsing out the function blocks when it imports the file. The downside though is that the file actually needs to be imported. Depending on where your files are coming from, this could introduce a HUGE security hole in your program -- You'll be running (potentially) "untrusted" code.
Here's a very non pythonic way, untested, but it should work.
sample = "foo.apples"
infile = open("file1.py", "r")
outfile = open("file2.txt", "w")
in_function = False
for line in infile.readlines():
if in_function:
if line[0] in(" ", "\t"):
if sample in line:
outfile.write(line)
else:
in_function = False
elif line.strip() == "def start():":
in_function = True
infile.close()
outfile.close()
I would suggest doing a function of this, which takes sample, the input file, and the function which we're supposed to search from as it's parameters. It would then return a list or tuple of all the lines that had the text in them.
def findFromFile(file, word, function):
in_function = False
matches = []
infile = open(file, "r")
for line in infile.readlines():
if in_function:
if line[0] in(" ", "\t"):
if word in line:
matches.append(line)
else:
in_function = False
elif line.strip() == "def %s():"%function:
in_function = True
infile.close()
return matches