I have two regular expressions:
$ grep -E '\-\- .*$' *.sql
$ sed -E '\-\- .*$' *.sql
(I am trying to grep lines in sql files that have comments and remove lines in sql files that have comments)
The grep command works using this regex; however, the sed returns the following error:
sed: -e expression #1, char 7: unterminated address regex
What am I doing incorrectly with sed?
(The space after the two hyphens is required for sql comments if you are unfamiliar with MySql comments of this type)
You're trying to use:
sed -E '\-\- .*$' *.sql
Here sed command is not correct because you're not really telling sed to do something.
It should be:
sed -n '/-- /p' *.sql
and equivalent grep would be:
grep -- '-- ' *.sql
or even better with a fixed string search:
grep -F -- '-- ' *.sql
Using -- to separate pattern and arguments in grep command.
There is no need to escape - in a regex if it is outside bracket expression (or character class) i.e. [...].
Based on comments below it seems OP's intent is to remove commented section in all *.sql files that start with 2 hyphens.
You may use this sed for that:
sed -i 's/-- .*//g' *.sql
The problem here is not the regex, the problem is that sed requires a command. The equivalent of your grep would be:
sed -n '/\-\- .*$/p'
You suppress output for non-matching lines -n ... you search (wrap your regex in slashes) and you print p (after the last slash).
P.S.: As Anub pointed out, escaping the hyphens - inside the regex is unnecessary.
You are trying to use sed's \cregexpc syntax where with \-<...> you are telling sed the delimiter character you want use is a dash -, but you didn't terminate it where it should be: \-<...>- also add d command to delete those lines.
sed '\-\-\-.*$-d' infile
see man sed about that:
\cregexpc
Match lines matching the regular expression regexp. The c may be any character.
if default / was used this was not required so:
sed '/--.*$/d' infile
or simply:
sed '/^--/d' infile
and more accurately:
sed '/^[[:blank:]]*--/d' infile
Using Sed I tried but it did not worked out.
Basically, I have a string say:-
Input:-
'http://www.google.com/photos'
Output required:-
http://www.google.com
I tried using sed but escaping ' is not possible.
what i did was:-
sed 's/\'//' | sed 's/photos//'
sed for photos worked but for ' it didn't.
Please suggest what can be the solution.
Escaping ' in sed is possible via a workaround:
sed 's/'"'"'//g'
# |^^^+--- bash string with the single quote inside
# | '--- return to sed string
# '------- leave sed string and go to bash
But for this job you should use tr:
tr -d "'"
Perl Replacements have a syntax identical to sed, works better than sed, is installed almost in every system by default and works for all machines the same way (portability):
$ echo "'http://www.google.com/photos'" |perl -pe "s#\'##g;s#(.*//.*/)(.*$)#\1#g"
http://www.google.com/
Mind that this solution will keep only the domain name with http in front, discarding all words following http://www.google.com/
If you want to do it with sed , you can use sed "s/'//g" as advised by Wiktor Stribiżew in comments.
PS: I sometimes refer to special chars with their ascii hex code of the special char as advised by man ascii, which is \x27 for '
So for sed you can do it:
$ echo "'http://www.google.com/photos'" |sed -r "s#'##g; s#(.*//.*/)(.*$)#\1#g;"
http://www.google.com/
# sed "s#\x27##g' will also remove the single quote using hex ascii code.
$ echo "'http://www.google.com/photos'" |sed -r "s#'##g; s#(.*//.*)(/.*$)#\1#g;"
http://www.google.com #Without the last slash
If your string is stored in a variable, you can achieve above operations with pure bash, without the need of external tools like sed or perl like this:
$ a="'http://www.google.com/photos'" && a="${a:1:-1}" && echo "$a"
http://www.google.com/photos
# This removes 1st and last char of the variable , whatever this char is.
$ a="'http://www.google.com/photos'" && a="${a:1:-1}" && echo "${a%/*}"
http://www.google.com
#This deletes every char from the end of the string up to the first found slash /.
#If you need the last slash you can just add it to the echo manually like echo "${a%/*}/" -->http://www.google.com/
It's unclear if the ' are actually around your string, although this should take care it:
str="'http://www.google.com/photos'"
echo "$str" | sed s/\'//g | sed 's/\/photos//g'
Combined:
echo "$str" | sed -e "s/'//g" -e 's/\/photos//g'
Using tr:
echo "$str" | sed -e "s/\/photos//g" | tr -d \'
Result:
http://www.google.com
If the single quotes are not around your string it should work regardless.
So I have the following string in my config.fish, and init.vim:
Fish: eval sh ~/.config/fish/colors/base16-monokai.dark.sh
Vim: colorscheme base16-monokai
Vim: let g:airline_theme='base16_monokai'
And I have the following shell script:
#!/bin/sh
theme=$1
background=$2
if [ -z '$theme' ]; then
echo "Please provide a theme name."
else
if [ -z '$background' ]; then
$background = 'dark'
fi
base16-builder -s $theme -t vim -b $background > ~/.config/nvim/colors/base16-$theme.vim &&
base16-builder -s $theme -t shell -b $background > ~/.config/fish/colors/base16-$theme.$background.sh &&
base16-builder -s $theme -t vim-airline -b $background > ~/.vim/plugged/vim-airline-themes/autoload/airline/themes/base16_$theme.vim
sed -i -e 's/foo/eval sh ~/.config/fish/colors/base16-$theme.$background.sh/g' ~/Developer/dotfiles/config.fish
sed -i -e 's/foo/colorscheme base16-$theme/g' ~/Developer/dotfiles/init.vim
sed -i -e 's/foo/let g:airline_theme='base16_$theme'/g' ~/Developer/dotfiles/init.vim
fi
Basically the idea is the script will generate whichever theme is passed through using this builder.
I have tried referring this documentation but I am not very skilled at regex so if anybody could give me a hand I would appreciate it.
What I need to happen is once the script is generated sed will look for the above strings and replace theme with the newly generated theme ones.
Try this :
sed -i "s|\(eval sh ~/\.config/fish/colors/base16-\)\([^.]*\)\.\([^.]*\)\\(.*\)|\1$theme.$background\4|
" ~/Developer/dotfiles/config.fish
sed -i "s/\(base16\)\([-_]\)\([a-zA-Z]*\)/\1\2$theme/g" ~/Developer/dotfiles/init.vim
Assuming in the second sed command that the theme is an alphanumeric string. If not, you can complete the character range : [a-zA-Z] with additional characters (eg [a-zA-Z0-9]).
You can replace something in sed using this syntax: sed "s#regex#replacement#g". Because you have /s and 's in your strings, it's easiest not to need to escape them.
There are some characters that need to be escaped to make the regexes. . and $ need to be escaped with a \. The $ in the replacement string needs to be escaped too.
If you want to capture a certain part from match, it's easiest to use char classes. For example, eval sh ~/\.config/fish/colors/base16-([^.]+)\.dark\.sh would be the regex to use if you want your replacement to be airline_theme='$1_base16_\$theme'. In that case, the $1 in the replacement is the thing captured in the regex.
[^.]+ will capture everything up to the next .
I hope this helps you to better understand regexes! This should be detailed enough to show you how to write your own.
You need to use double quotes for parameter expansion not single quotes.
You need to escape the single quotes: 'hello'\''world'
I will make one line for you and leave it as an exercise to fix the other lines
sed -i -e 's~\(let g:airline_theme='\''\)[^'\'']*\('\'\)'~base16_'"$theme"~' ~/Developer/dotfiles/init.vim
The first character after the s in the sed expression string is used as the pattern separator, so by putting / first you have specified / as the separator.
Additionally using the single quote tells the shell not to expand any variables, you are going to want to use double quotes instead.
try something like
sed -i -e "s#foo#eval sh ~/.config/fish/colors/base16-$theme.$background.sh#g" ~/Developer/dotfiles/config.fish
as you've now commented that you needed to find the previous theme string instead of foo
sed -i -e "s#eval sh \~/\.config/fish/colors/base16-.*?\..*?\.sh#eval sh ~/.config/fish/colors/base16-$theme.$background.sh#g" ~/Developer/dotfiles/config.fish
I want to replace $_SERVER['DB_NAME'] with just the word test using sed. I cannot figure it out. I am escaping the $ and brackets...why am I not getting the correct result?
echo "\$_SERVER['DB_NAME']" | sed 's/\$_SERVER\['DB_NAME'\]/test/g'
You can try this
echo "\$_SERVER['DB_NAME']" | sed "s/\$_SERVER\['DB_NAME'\]/test/g"
or
echo "\$_SERVER['DB_NAME']" | sed 's/\$_SERVER\['"'"'DB_NAME'"'"'\]/test/g'
You're using single quotes for both the sed command and the 'DB_NAME'. Change the quotes around the sed command line to double quotes or escape the inner quotes.
I've got a CSV file that looks like:
1,3,"3,5",4,"5,5"
Now I want to change all the "," not within quotes to ";" with sed, so it looks like this:
1;3;"3,5";5;"5,5"
But I can't find a pattern that works.
If you are expecting only numbers then the following expression will work
sed -e 's/,/;/g' -e 's/\("[0-9][0-9]*\);\([0-9][0-9]*"\)/\1,\2/g'
e.g.
$ echo '1,3,"3,5",4,"5,5"' | sed -e 's/,/;/g' -e 's/\("[0-9][0-9]*\);\([0-9][0-9]*"\)/\1,\2/g'
1;3;"3,5";4;"5,5"
You can't just replace the [0-9][0-9]* with .* to retain any , in that is delimted by quotes, .* is too greedy and matches too much. So you have to use [a-z0-9]*
$ echo '1,3,"3,5",4,"5,5",",6","4,",7,"a,b",c' | sed -e 's/,/;/g' -e 's/\("[a-z0-9]*\);\([a-z0-9]*"\)/\1,\2/g'
1;3;"3,5";4;"5,5";",6";"4,";7;"a,b";c
It also has the advantage over the first solution of being simple to understand. We just replace every , by ; and then correct every ; in quotes back to a ,
You could try something like this:
echo '1,3,"3,5",4,"5,5"' | sed -r 's|("[^"]*),([^"]*")|\1\x1\2|g;s|,|;|g;s|\x1|,|g'
which replaces all commas within quotes with \x1 char, then replaces all commas left with semicolons, and then replaces \x1 chars back to commas. This might work, given the file is correctly formed, there're initially no \x1 chars in it and there're no situations where there is a double quote inside double quotes, like "a\"b".
Using gawk
gawk '{$1=$1}1' FPAT="([^,]+)|(\"[^\"]+\")" OFS=';' filename
Test:
[jaypal:~/Temp] cat filename
1,3,"3,5",4,"5,5"
[jaypal:~/Temp] gawk '{$1=$1}1' FPAT='([^,]+)|(\"[^\"]+\")' OFS=';' filename
1;3;"3,5";4;"5,5"
This might work for you:
echo '1,3,"3,5",4,"5,5"' |
sed 's/\("[^",]*\),\([^"]*"\)/\1\n\2/g;y/,/;/;s/\n/,/g'
1;3;"3,5";4;"5,5"
Here's alternative solution which is longer but more flexible:
echo '1,3,"3,5",4,"5,5"' |
sed 's/^/\n/;:a;s/\n\([^,"]\|"[^"]*"\)/\1\n/;ta;s/\n,/;\n/;ta;s/\n//'
1;3;"3,5";4;"5,5"