CODEWITHSUNDEEP
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Nesousx
Nesousx

Reputation: 73

Converting a list to double quoted comma separated strings

I have a problem I can't seem able to fix by myself, nor by searching the internets.

I have a list, stored in a file, like this:

apple
banana
pineapple

And I would like each string to be in double quote, and comma separated, like this:

"apple","banana","pineapple"

Ideally, the last word of the list shouldn't have a comma after it, but this is not mandatory.

The idea behind this is to be able to create a JSON formatted document populated by a list of item stored in a plain text file.

Thanks a lot in advance.

Upvotes: 7

Views: 4143

Answers (6)

Petr Razumov
Petr Razumov

Reputation: 2142

sed and paste solution:

sed -e 's/^\|$/"/g' file | paste -s -d, -

Upvotes: 2

user3442743
user3442743

Reputation:

No fancy stuff awk:

awk 'x{x=x","}{x=x"\""$1"\""}END{print x}' file

Explained version:

awk '
  out { out = out "," }           # if there is already something in the output string, append a comma to it
      { out = out "\"" $1 "\"" }  # always append the quoted first column of input to the output string
  END { print out }               # finally, print the output string
' file

The peculiar ordering of the first two lines matters - it prevents the final comma from being appended.

Upvotes: 0

Kalanidhi
Kalanidhi

Reputation: 5092

You can also use this method:

sed -r ':loop ; N ; s/\n/,/g ; $s/[^,]+/"&"/g ; t loop' filename

Upvotes: 1

Tom Fenech
Tom Fenech

Reputation: 74595

I think that Perl also deserves a mention:

perl -lne 'push @a, qq("$_") }{ print join(",", @a)' file

Builds an array @a containing the value on each line, wrapped in double quotes. Then once the file has been processed, prints out a comma separated list of all the elements in @a.

The so-called eskimo greeting }{ is a shorthand used to create an END block, due to the way that the -n and -p switches are implemented.

Output:

"apple","banana","pineapple"

If it's JSON you're looking for, you could use encode_json:

perl -MJSON -lne 'push @a, $_ }{ print encode_json(\@a)' file

This turns the array into a real JSON-encoded list:

["apple","banana","pineapple"]

Upvotes: 2

konsolebox
konsolebox

Reputation: 75478

awk -v RS='' -v OFS='","' 'NF { $1 = $1; print "\"" $0 "\"" }' file

Output:

"apple","banana","pineapple"

Upvotes: 7

Jotne
Jotne

Reputation: 41446

Another awk

awk '{printf "\"%s\"",$1}' file | awk '{gsub(/""/,"\",\"")}1'
"apple","banana","pineapple"

or

awk '{printf "\"%s\"",$1}' file | sed 's/""/","/g'

Upvotes: 0

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