yet another append question

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February 8th, 2004, 10:53 AM

Boceifus

Contributing User

Join Date: Jan 2004

Posts: 103

Time spent in forums: 3 Days 1 h 17 m 20 sec
Reputation Power: 10

yet another append question

greets

i found this handy function by Netytan to insert strings into a text file.

Code:

#Netytan Insert Function

def sappend(file, string, line = 0, out = file):
	file = open(file, 'r').readlines()
	file.insert(line, string)
	open(out, 'w').writelines(file)

sappend('file.txt', 'baby\n', 3, 'new.txt')

works great,but i have just a few questions.please forgive me if my wording is incorrect.

1)can i make the string replace the line,not just insert the string into the line?

2)is there a way i can make the line number a result of raw_input?i am trying to do something like: sappend(fn, string, ln, fn2)

Code:

def sappend(file, string, line = 0, out = file):
    
	file = open(file, 'r').readlines()
	file.insert(line, string)
	open(out, 'w').writelines(file)


fn= raw_input('file to edit?')
fn2= raw_input('save name?')
ln= raw_input('line number?')
string= raw_input('string to add?')

sappend (fn, string, ln, fn2)

but i get this error when i use "ln" in the sappend line:
TypeError: an integer is required

but "ln" IS a number...can anyone please help?thx in advance

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February 8th, 2004, 12:43 PM

netytan

Hello World :)

Join Date: Mar 2003

Location: Hull, UK

Posts: 2,537

Time spent in forums: 1 Week 2 Days 18 h 17 m 47 sec
Reputation Power: 68

because of the nature of the insert method you can't really make it replace the line but you can simply overwrite the value of that line like so...

Code:

def rappend(path, string, index = 0, output = path):
	lines = file(path, 'r').readlines()
	lines[index] = string
	file(output, 'w').writelines(lines)

The reason you're getting an error using raw_input() is because raw_input() always returns a string; even if a number was entered. So u need to type-cast your value using int().

Code:

>>> value = raw_input('line number')
line number10
>>> value
'10'
>>> int(value)
10
>>>

Let me know if you have any questions.

Mark.

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February 8th, 2004, 05:18 PM

Boceifus

Contributing User

Join Date: Jan 2004

Posts: 103

Time spent in forums: 3 Days 1 h 17 m 20 sec
Reputation Power: 10

thank you netytan...rappend works like a charm

and thank you for explaining how raw_input always returns strings,even if the input is a integer.

cheers!

yet another append question

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