pyparsing: match words on same line - whitespace

In pyparsing I'm looking for a simple way to match words (or other expressions) that occur on the same line, i.e. without any newline in between them.

You can override the default whitespace-skipping characters for a particular parser element - in this case, the word_on_the_same_line only skips spaces, but not newlines.
import pyparsing as pp
word = pp.Word(pp.alphas, pp.alphanums)
# define special whitespace skipping, so that newlines aren't
# skipped when matching a word_on_the_same_line
word_on_the_same_line = word().setWhitespaceChars(" ")
# compare results with this version of word_on_the_same_line to see
# how pyparsing treats newlines as skippable whitespace
# word_on_the_same_line = word()
line = pp.Group(word("key") + word_on_the_same_line[...]("values"))
test = """\
key1 lsdkjf lskdjf lskjdf sldkjf
key2 sdlkjf lskdj lkjss lsdj
"""
print(line[...].parseString(test).dump())
Prints:
[['key1', 'lsdkjf', 'lskdjf', 'lskjdf', 'sldkjf'], ['key2', 'sdlkjf', 'lskdj', 'lkjss', 'lsdj']]
[0]:
['key1', 'lsdkjf', 'lskdjf', 'lskjdf', 'sldkjf']
- key: 'key1'
- values: ['lsdkjf', 'lskdjf', 'lskjdf', 'sldkjf']
[1]:
['key2', 'sdlkjf', 'lskdj', 'lkjss', 'lsdj']
- key: 'key2'
- values: ['sdlkjf', 'lskdj', 'lkjss', 'lsdj']

Related

Sort two text files with its indented text aligned to it

I would like to compare two of my log files generated before and after an implementation to see if it has impacted anything. However, the order of the logs I get is not the same all the time. Since, the log file also has multiple indented lines, when I tried to sort, everything is sorted. But, I would like to keep the child intact with the parent. Indented lines are spaces and not tab.
Any help would be greatly appreciated. I am fine with any windows solution or Linux one.
Eg of the file:
#This is a sample code
Parent1 to be verified
Child1 to be verified
Child2 to be verified
Child21 to be verified
Child23 to be verified
Child22 to be verified
Child221 to be verified
Child4 to be verified
Child5 to be verified
Child53 to be verified
Child52 to be verified
Child522 to be verified
Child521 to be verified
Child3 to be verified
I am posting another answer here to sort it hierarchically, using python.
The idea is to attach the parents to the children to make sure that the children under the same parent are sorted together.
See the python script below:
"""Attach parent to children in an indentation-structured text"""
from typing import Tuple, List
import sys
# A unique separator to separate the parent and child in each line
SEPARATOR = '#'
# The indentation
INDENT = ' '
def parse_line(line: str) -> Tuple[int, str]:
"""Parse a line into indentation level and its content
with indentation stripped
Args:
line (str): One of the lines from the input file, with newline ending
Returns:
Tuple[int, str]: The indentation level and the content with
indentation stripped.
Raises:
ValueError: If the line is incorrectly indented.
"""
# strip the leading white spaces
lstripped_line = line.lstrip()
# get the indentation
indent = line[:-len(lstripped_line)]
# Let's check if the indentation is correct
# meaning it should be N * INDENT
n = len(indent) // len(INDENT)
if INDENT * n != indent:
raise ValueError(f"Wrong indentation of line: {line}")
return n, lstripped_line.rstrip('\r\n')
def format_text(txtfile: str) -> List[str]:
"""Format the text file by attaching the parent to it children
Args:
txtfile (str): The text file
Returns:
List[str]: A list of formatted lines
"""
formatted = []
par_indent = par_line = None
with open(txtfile) as ftxt:
for line in ftxt:
# get the indentation level and line without indentation
indent, line_noindent = parse_line(line)
# level 1 parents
if indent == 0:
par_indent = indent
par_line = line_noindent
formatted.append(line_noindent)
# children
elif indent > par_indent:
formatted.append(par_line +
SEPARATOR * (indent - par_indent) +
line_noindent)
par_indent = indent
par_line = par_line + SEPARATOR + line_noindent
# siblings or dedentation
else:
# We just need first `indent` parts of parent line as our prefix
prefix = SEPARATOR.join(par_line.split(SEPARATOR)[:indent])
formatted.append(prefix + SEPARATOR + line_noindent)
par_indent = indent
par_line = prefix + SEPARATOR + line_noindent
return formatted
def sort_and_revert(lines: List[str]):
"""Sort the formatted lines and revert the leading parents
into indentations
Args:
lines (List[str]): list of formatted lines
Prints:
The sorted and reverted lines
"""
sorted_lines = sorted(lines)
for line in sorted_lines:
if SEPARATOR not in line:
print(line)
else:
leading, _, orig_line = line.rpartition(SEPARATOR)
print(INDENT * (leading.count(SEPARATOR) + 1) + orig_line)
def main():
"""Main entry"""
if len(sys.argv) < 2:
print(f"Usage: {sys.argv[0]} <file>")
sys.exit(1)
formatted = format_text(sys.argv[1])
sort_and_revert(formatted)
if __name__ == "__main__":
main()
Let's save it as format.py, and we have a test file, say test.txt:
parent2
child2-1
child2-1-1
child2-2
parent1
child1-2
child1-2-2
child1-2-1
child1-1
Let's test it:
$ python format.py test.txt
parent1
child1-1
child1-2
child1-2-1
child1-2-2
parent2
child2-1
child2-1-1
child2-2
If you wonder how the format_text function formats the text, here is the intermediate results, which also explains why we could make file sorted as we wanted:
parent2
parent2#child2-1
parent2#child2-1#child2-1-1
parent2#child2-2
parent1
parent1#child1-2
parent1#child1-2#child1-2-2
parent1#child1-2#child1-2-1
parent1#child1-1
You may see that each child has its parents attached, all the way along to the root. So that the children under the same parent are sorted together.
Short answer (Linux solution):
sed ':a;N;$!ba;s/\n /#/g' test.txt | sort | sed ':a;N;$!ba;s/#/\n /g'
Test it out:
test.txt
parent2
child2-1
child2-1-1
child2-2
parent1
child1-1
child1-2
child1-2-1
$ sed ':a;N;$!ba;s/\n /#/g' test.txt | sort | sed ':a;N;$!ba;s/#/\n /g'
parent1
child1-1
child1-2
child1-2-1
parent2
child2-1
child2-1-1
child2-2
Explanation:
The idea is to replace the newline followed by an indentation/space with a non newline character, which has to be unique in your file (here I used # for example, if it is not unique in your file, use other characters or even a string), because we need to turn it back the newline and indentation/space later.
About sed command:
:a create a label 'a'
N append the next line to the pattern space
$! if not the last line, ba branch (go to) label 'a'
s substitute, /\n / regex for newline followed by a space
/#/ a unique character to replace the newline and space
if it is not unique in your file, use other characters or even a string
/g global match (as many times as it can)

Replace pattern in string with value from a ruby array

I have a string like this
"base: [_0x3e63[241], _0x3e63[242]],
gray: [_0x3e63[243], _0x3e63[244], _0x3e63[245], _0x3e63[246], _0x3e63[247], _0x3e63[248], _0x3e63[249], _0x3e63[250], _0x3e63[251], _0x3e63[252]],
red: [_0x3e63[253], _0x3e63[254], _0x3e63[255], _0x3e63[256], _0x3e63[257], _0x3e63[258], _0x3e63[259], _0x3e63[260], _0x3e63[261], _0x3e63[262]],
pink: [_0x3e63[263], _0x3e63[264], _0x3e63[265], _0x3e63[266], _0x3e63[267], _0x3e63[268], _0x3e63[269], _0x3e63[270], _0x3e63[271], _0x3e63[272]],
grape: [_0x3e63[273], _0x3e63[274], _0x3e63[275], _0x3e63[276], _0x3e63[277], _0x3e63[278], _0x3e63[279], _0x3e63[280], _0x3e63[281], _0x3e63[282]],
violet: [_0x3e63[283], _0x3e63[284], _0x3e63[285], _0x3e63[286], _0x3e63[287], _0x3e63[288], _0x3e63[289], _0x3e63[290], _0x3e63[291], _0x3e63[292]],
indigo: [_0x3e63[293], _0x3e63[294], _0x3e63[295], _0x3e63[296], _0x3e63[297], _0x3e63[298], _0x3e63[299], _0x3e63[300], _0x3e63[301], _0x3e63[302]],
blue: [_0x3e63[303], _0x3e63[304], _0x3e63[305], _0x3e63[306], _0x3e63[307], _0x3e63[308], _0x3e63[309], _0x3e63[310], _0x3e63[311], _0x3e63[312]],
cyan: [_0x3e63[313], _0x3e63[314], _0x3e63[315], _0x3e63[316], _0x3e63[317], _0x3e63[318], _0x3e63[319], _0x3e63[320], _0x3e63[321], _0x3e63[322]],
teal: [_0x3e63[323], _0x3e63[324], _0x3e63[325], _0x3e63[326], _0x3e63[327], _0x3e63[328], _0x3e63[329], _0x3e63[330], _0x3e63[331], _0x3e63[332]],
green: [_0x3e63[333], _0x3e63[334], _0x3e63[335], _0x3e63[336], _0x3e63[337], _0x3e63[338], _0x3e63[339], _0x3e63[340], _0x3e63[341], _0x3e63[342]],
lime: [_0x3e63[343], _0x3e63[344], _0x3e63[345], _0x3e63[346], _0x3e63[347], _0x3e63[348], _0x3e63[349], _0x3e63[350], _0x3e63[351], _0x3e63[352]],
yellow: [_0x3e63[353], _0x3e63[354], _0x3e63[355], _0x3e63[356], _0x3e63[357], _0x3e63[358], _0x3e63[359], _0x3e63[360], _0x3e63[361], _0x3e63[362]],
orange: [_0x3e63[363], _0x3e63[364], _0x3e63[365], _0x3e63[366], _0x3e63[367], _0x3e63[368], _0x3e63[369], _0x3e63[370], _0x3e63[371], _0x3e63[372]]"
_0x3e63 is a ruby array with the values.
_0x3e63 = ["#f783ac", "#faa2c1", "#fcc2d7", "#ffdeeb", "#fff0f6", "#862e9c", "#9c36b5", "#ae3ec9", "#be4bdb", "#cc5de8", "#da77f2", "#e599f7", "#eebefa", "#f3d9fa", "#f8f0fc", "#5f3dc4", "#6741d9", "#7048e8", "#7950f2", "#845ef7", "#9775fa", "#b197fc", "#d0bfff", "#e5dbff", "#f3f0ff", "#364fc7", "#3b5bdb", "#4263eb", "#4c6ef5", "#5c7cfa", "#748ffc", "#91a7ff", "#bac8ff", "#dbe4ff", "#edf2ff", "#1864ab", "#1971c2", "#1c7ed6", "#228be6", "#339af0", "#4dabf7", "#74c0fc", "#a5d8ff", "#d0ebff", "#e7f5ff", "#0b7285", "#0c8599", "#1098ad", "#15aabf", "#22b8cf", "#3bc9db", "#66d9e8", "#99e9f2", "#c5f6fa", "#e3fafc", "#087f5b", "#099268", "#0ca678", "#12b886", "#20c997", "#38d9a9", "#63e6be", "#96f2d7", "#c3fae8", "#e6fcf5", "#2b8a3e", "#2f9e44", "#37b24d", "#40c057", "#51cf66", "#69db7c", "#8ce99a", "#b2f2bb", "#d3f9d8", "#ebfbee", "#5c940d", "#66a80f", "#74b816", "#82c91e", "#94d82d", "#a9e34b", "#c0eb75", "#d8f5a2", "#e9fac8", "#f4fce3", "#e67700", "#f08c00", "#f59f00", "#fab005", "#fcc419", "#ffd43b", "#ffe066", "#ffec99", "#fff3bf", "#fff9db", "#d9480f", "#e8590c"]
I cannot find a way to retrieve from the string _0x3e63[xxxxxxx] replacing it with the right value....
Use String#gsub with a block.
Assuming your input string is stored in the variable input, the following code does the replacement and displays the result:
puts input.gsub(/_0x3e63\[(\d+)\]/){|s| _0x3e63[$1.to_i]}
(The array _0x3e63 you posted in the question does not contain enough values to have indices like 247 or 251 but the code works nevertheless.)
The code is very simple. The regular expression /_0x3e63\[(\d+)\]/ matches any string that starts with _0x3e63[, continues with one or more digits (\d+) and ends with ].
For each match the block is executed and the value returned by the block is used to replace the matched piece of the original string.
The replacement uses $1 (that contains the sub-string that matches the first capturing group) as an index into the array _0x3e63. Because the value of $1 is a string, .to_i is used to convert it to a number (required to be used as index in the array).
We are given:
str =<<~END
base: [arr[6], arr[3]],
gray: [arr[0], arr[4], arr[1], arr[5]],
red: [arr[2]]
END
#=> "base: [arr[6], arr[3]],\ngray: [arr[0], arr[4], arr[1], arr[5]],\nred: [arr[2]]\n"
and
arr = ["#f783ac", "#faa2c1", "#fcc2d7", "#ffdeeb", "#fff0f6", "#862e9c",
"#9c36b5"]
We can perform the required replacements by using String#gsub with a regular expression and Kernel#eval:
puts str.gsub(/\barr\[\d+\]/) { |s| eval s }
base: [#9c36b5, #ffdeeb],
gray: [#f783ac, #fff0f6, #faa2c1, #862e9c],
red: [#fcc2d7]
The regular expression preforms the following operations:
\b # match a word break (to avoid matching 'gnarr')
arr\[ # match string 'arr['
\d+ # match 1+ digits
\] # match ']'
Rubular
One must be cautious about using eval (to avoid launching missiles inadvertently, for example), but as long as the matches of the string can be trusted it's a perfectly safe and useful method.

How to parse username, ID or whole part using Ruby Regex in this sentence?

I have a sentences like this:
Hello #[Pratha](user:1), did you see #[John](user:3)'s answer?
And what I want to is get #[Pratha](user:1) and #[John](user:3). Either their names and ids or just as texts as I quoted so that i can explode and parse name and id myself.
But there is an issue here. Names Pratha and John may include non-abc characters like ', ,, -, + , etc... But not [] and ()
What I tried so far:
c = ''
f = c.match(/(?:\s|^)(?:#(?!(?:\d+|\w+?_|_\w+?)(?:\s(\[)|$)))(\w+)(?=\s|$)/i)
But no success.
You may use
/#\[([^\]\[]*)\]\([^()]*:(\d+)\)/
See the regex demo
Details
# - a # char
\[ - a [
([^\]\[]*) - Group 1: 0+ chars other than [ and ]
\] - a ] char
\( - a ( char
[^()]*- 0+ chars other than ( and )
: - a colon
(\d+) - Group 2: 1 or more digits
\) - a ) char.
Sample Ruby code:
s = "Hello #[Pratha](user:1), did you see #[John](user:3)'s answer?"
rx = /#\[([^\]\[]*)\]\([^()]*:(\d+)\)/
res = s.scan(rx)
puts res
# = > [["Pratha", "1"], ["John", "3"]]
"Hello #[Pratha](user:1), did you see #[John](user:3)'s answer?".scan(/#.*?\)/)
#⇒ ["#[Pratha](user:1)", "#[John](user:3)"]
Since the line is not coming from the user input, you might rely on that the part you are interested in starts with # and ends with ).
You could use 2 capturing groups to get the names and the id's:
#\[([^]]+)]\([^:]+:([^)]+)\)
That will match
# Match literally
\[ Match [
([^]]+) 1st capturing group which matches not ] 1+ times using a negated character class.
\( Match literally
[^:]+: Match not :, then match :
([^)]+) 2nd capturing group which matches not ) 1+ times
\) Match )
Regex demo | Ruby demo

Ruby Regex find numbers not surrounded by alphabetical characters [duplicate]

I have a regex expression that I'm using to find all the words in a given block of content, case insensitive, that are contained in a glossary stored in a database. Here's my pattern:
/($word)/i
The problem is, if I use /(Foo)/i then words like Food get matched. There needs to be whitespace or a word boundary on both sides of the word.
How can I modify my expression to match only the word Foo when it is a word at the beginning, middle, or end of a sentence?
Use word boundaries:
/\b($word)\b/i
Or if you're searching for "S.P.E.C.T.R.E." like in Sinan Ünür's example:
/(?:\W|^)(\Q$word\E)(?:\W|$)/i
To match any whole word you would use the pattern (\w+)
Assuming you are using PCRE or something similar:
Above screenshot taken from this live example: http://regex101.com/r/cU5lC2
Matching any whole word on the commandline with (\w+)
I'll be using the phpsh interactive shell on Ubuntu 12.10 to demonstrate the PCRE regex engine through the method known as preg_match
Start phpsh, put some content into a variable, match on word.
el#apollo:~/foo$ phpsh
php> $content1 = 'badger'
php> $content2 = '1234'
php> $content3 = '$%^&'
php> echo preg_match('(\w+)', $content1);
1
php> echo preg_match('(\w+)', $content2);
1
php> echo preg_match('(\w+)', $content3);
0
The preg_match method used the PCRE engine within the PHP language to analyze variables: $content1, $content2 and $content3 with the (\w)+ pattern.
$content1 and $content2 contain at least one word, $content3 does not.
Match a number of literal words on the commandline with (dart|fart)
el#apollo:~/foo$ phpsh
php> $gun1 = 'dart gun';
php> $gun2 = 'fart gun';
php> $gun3 = 'farty gun';
php> $gun4 = 'unicorn gun';
php> echo preg_match('(dart|fart)', $gun1);
1
php> echo preg_match('(dart|fart)', $gun2);
1
php> echo preg_match('(dart|fart)', $gun3);
1
php> echo preg_match('(dart|fart)', $gun4);
0
variables gun1 and gun2 contain the string dart or fart. gun4 does not. However it may be a problem that looking for word fart matches farty. To fix this, enforce word boundaries in regex.
Match literal words on the commandline with word boundaries.
el#apollo:~/foo$ phpsh
php> $gun1 = 'dart gun';
php> $gun2 = 'fart gun';
php> $gun3 = 'farty gun';
php> $gun4 = 'unicorn gun';
php> echo preg_match('(\bdart\b|\bfart\b)', $gun1);
1
php> echo preg_match('(\bdart\b|\bfart\b)', $gun2);
1
php> echo preg_match('(\bdart\b|\bfart\b)', $gun3);
0
php> echo preg_match('(\bdart\b|\bfart\b)', $gun4);
0
So it's the same as the previous example except that the word fart with a \b word boundary does not exist in the content: farty.
Using \b can yield surprising results. You would be better off figuring out what separates a word from its definition and incorporating that information into your pattern.
#!/usr/bin/perl
use strict; use warnings;
use re 'debug';
my $str = 'S.P.E.C.T.R.E. (Special Executive for Counter-intelligence,
Terrorism, Revenge and Extortion) is a fictional global terrorist
organisation';
my $word = 'S.P.E.C.T.R.E.';
if ( $str =~ /\b(\Q$word\E)\b/ ) {
print $1, "\n";
}
Output:
Compiling REx "\b(S\.P\.E\.C\.T\.R\.E\.)\b"
Final program:
1: BOUND (2)
2: OPEN1 (4)
4: EXACT (9)
9: CLOSE1 (11)
11: BOUND (12)
12: END (0)
anchored "S.P.E.C.T.R.E." at 0 (checking anchored) stclass BOUND minlen 14
Guessing start of match in sv for REx "\b(S\.P\.E\.C\.T\.R\.E\.)\b" against "S.P
.E.C.T.R.E. (Special Executive for Counter-intelligence,"...
Found anchored substr "S.P.E.C.T.R.E." at offset 0...
start_shift: 0 check_at: 0 s: 0 endpos: 1
Does not contradict STCLASS...
Guessed: match at offset 0
Matching REx "\b(S\.P\.E\.C\.T\.R\.E\.)\b" against "S.P.E.C.T.R.E. (Special Exec
utive for Counter-intelligence,"...
0 | 1:BOUND(2)
0 | 2:OPEN1(4)
0 | 4:EXACT (9)
14 | 9:CLOSE1(11)
14 | 11:BOUND(12)
failed...
Match failed
Freeing REx: "\b(S\.P\.E\.C\.T\.R\.E\.)\b"
For Those who want to validate an Enum in their code you can following the guide
In Regex World you can use ^ for starting a string and $ to end it. Using them in combination with | could be what you want :
^(Male)$|^(Female)$
It will return true only for Male or Female case.
If you are doing it in Notepad++
[\w]+
Would give you the entire word, and you can add parenthesis to get it as a group. Example: conv1 = Conv2D(64, (3, 3), activation=LeakyReLU(alpha=a), padding='valid', kernel_initializer='he_normal')(inputs). I would like to move LeakyReLU into its own line as a comment, and replace the current activation. In notepad++ this can be done using the follow find command:
([\w]+)( = .+)(LeakyReLU.alpha=a.)(.+)
and the replace command becomes:
\1\2'relu'\4 \n # \1 = LeakyReLU\(alpha=a\)\(\1\)
The spaces is to keep the right formatting in my code. :)
use word boundaries \b,
The following (using four escapes) works in my environment: Mac, safari Version 10.0.3 (12602.4.8)
var myReg = new RegExp(‘\\\\b’+ variable + ‘\\\\b’, ‘g’)
Get all "words" in a string
/([^\s]+)/g
Basically ^/s means break on spaces (or match groups of non-spaces)
Don't forget the g for Greedy
Try it:
"Not the answer you're looking for? Browse other questions tagged regex word-boundary or ask your own question.".match(/([^\s]+)/g)
→ (17) ['Not', 'the', 'answer', "you're", 'looking', 'for?', 'Browse', 'other', 'questions', 'tagged', 'regex', 'word-boundary', 'or', 'ask', 'your', 'own', 'question.']

Ruby replace array list

I have two strings:
packages="­linux-imag­e-3.2.0-4-­amd64 linux­-libc-dev linux­-headers-3­.2.0-4-amd­64 linux­-headers-3­.2.0-4-com­mon dnsutils mysql-server-5.5"
exclusion="dnsutils mysql-server-5.5"
I need a string pkgs that has the content of packages without exclusion like this:
pkgs="­linux-imag­e-3.2.0-4-­amd64 linux­-libc-dev linux­-headers-3­.2.0-4-amd­64 linux­-headers-3­.2.0-4-com­mon"
I tried the following code:
pkgs = packages.gsub!( /(?<!^|,)#{exclusion}(?!,|$)/, '\1')
which does not seem to be working. What would be the best working solution in this case?
packages="linux-image-3.2.0-4-amd64 linux-libc-dev linux-headers-3.2.0-4-amd64 linux-headers-3.2.0-4-common dnsutils mysql-server-5.5"
exclusion="dnsutils mysql-server-5.5"
(packages.split - exclusion.split).join(" ") # => "linux-image-3.2.0-4-amd64 linux-libc-dev linux-headers-3.2.0-4-amd64 linux-headers-3.2.0-4-common"
You need your variables to be arrays, not strings. Then you can just use the - operator to "subtract" the items in exclusion from packages:
packages = [ "­linux-imag­e-3.2.0-4-­amd64",
"linux­-libc-dev",
"linux­-headers-3­.2.0-4-amd­64",
"linux­-headers-3­.2.0-4-com­mon",
"dnsutils",
"mysql-server-5.5" ]
exclusion = [ "dnsutils", "mysql-server-5.5" ]
remaining = packages - exclusion
# => [ "­linux-imag­e-3.2.0-4-­amd64",
# "linux­-libc-dev",
# "linux­-headers-3­.2.0-4-amd­64",
# "linux­-headers-3­.2.0-4-com­mon" ]
If you then need the values in a single string, join them together with the join method:
remaining_str = remaining.join(" ")
# => "­linux-imag­e-3.2.0-4-­amd64 linux­-libc-dev linux­-headers-3­.2.0-4-amd­64 linux­-headers-3­.2.0-4-com­mon"
If you want to keep it simple, you can always split these strings into arrays, and join the difference.
(packages.split - exclusion.split).join ' '
String's split method will default to space characters. This give you two arrays, where you subtract the any values that exist in the both the first and second array from the first array. You then join this new array with space characters.
Longer example:
packages="linux-image-3.2.0-4-amd64 linux-libc-dev linux-headers-3.2.0-4-amd64 linux-headers-3.2.0-4-common dnsutils mysql-server-5.5"
exclusion="dnsutils mysql-server-5.5"
one = packages.split
# >> ["linux-image-3.2.0-4-amd64", "linux-libc-dev", "linux-headers-3.2.0-4-amd64", "linux-headers-3.2.0-4-common", "dnsutils", "mysql-server-5.5"]
two = exclusion.split
# >> ["dnsutils", "mysql-server-5.5"]
difference = one - two
# >> ["linux-image-3.2.0-4-amd64", "linux-libc-dev", "linux-headers-3.2.0-4-amd64", "linux-headers-3.2.0-4-common"]
finished = difference.join ' '
# >> "linux-image-3.2.0-4-amd64 linux-libc-dev linux-headers-3.2.0-4-amd64 linux-headers-3.2.0-4-common"

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