How to ignore last newline in multiline line with Perl

Question

I need to turn foo,bar

into

BAZ(foo) \
BAZ(bar)

\

there is as-is.

I tried with echo 'foo,bar' | tr , '\n' | perl -pe 's/(.*)\n/BAZ($1) \\\n/g'

but created

BAZ(foo) \
BAZ(bar) \

So this is either a completely wrong approach, or I need a way to ignore the last newline in a multi-line string from Perl.

+3

regex shell perl sh

Marcel Stör May 18 '15 at 13:57

source to share

4 answers

You can use join

with map

for example:

$ echo 'foo,bar' | perl -F, -lape '$_ = join(" \\\n", map { "BAZ(" . $_ . ")" } @F)'
BAZ(foo) \
BAZ(bar)

-a

enables automatic split mode by splitting the input with a separator ,

and assigning it@F
map

takes each element of the array and wraps it
join

adds backslash and newline between each element

+3

Tom fenech May 18 '15 at 14:03

source to share

echo 'foo,bar' | perl -ne'print join " \\\n", map "BAZ($_)", /\w+/g'

Output

BAZ(foo) \
BAZ(bar)

+3

Borodin May 18 '15 at 14:06

source to share

Using awk

, you can:

s='foo,bar'
awk -F, '{for (i=1; i<=NF; i++) printf "BAZ(%s) %s\n", $i, (i<NF)? "\\" : ""}' <<< "$s"
BAZ(foo) \
BAZ(bar)

Or using sed

:

sed -r 's/([^,]+)$/BAZ(\1)/; s/([^,]+),/BAZ(\1) \\\n/g' <<< "$s"
BAZ(foo) \
BAZ(bar)

+1

anubhava 18 May '15 at 14:00

source to share

RobEarl · Accepted Answer · 2015-05-18T14:05:44+0000

Using eof

to determine if you are on the last line:

echo 'foo,bar' | tr , '\n' | perl -pe 'my $break = (eof) ? "" : "\\"; s/(.*)\n/BAZ($1) $break\n/g'