Must have CLI of Perl's sed's n command

abdan has asked for the wisdom of the Perl Monks concerning the following question:

How do we have CLI of Perl's sed's n command ?
e.g. illustration:

cat script.txt| perl -nle 'if (/^===\w+\s*$/){ next # ??? how to ignor
+e first $_, here eg. ===Hello, to directly become replaced by next li
+ne ; # ... } print'
[download]

Comment on Must have CLI of Perl's sed's n command Download Code

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Re: Must have CLI of Perl's sed's n command by Tux (Canon) on Jun 30, 2022 at 06:35 UTC
sed - Perl conversion done with s2p =head1 NAME psed - a stream editor =head1 SYNOPSIS psed [-an] script [file ...] psed [-an] [-e script] [-f script-file] [file ...] s2p [-an] [-e script] [-f script-file] =head1 DESCRIPTION A stream editor reads the input stream consisting of the specified fil +es (or standard input, if none are given), processes is line by line by applying a script consisting of edit commands, and writes resulting li +nes to standard output. The filename 'C<->' may be used to read standard i +nput. The edit script is composed from arguments of B<-e> options and script-files, in the given order. A single script argument may be spec +ified as the first parameter. If this program is invoked with the name F<s2p>, it will act as a sed-to-Perl translator. See L<"SED SCRIPT TRANSLATION">. B<sed> returns an exit code of 0 on success or >0 if an error occurred +. [download] Enjoy, Have FUN! H.Merijn	[reply] [d/l]
Re^2: Must have CLI of Perl's sed's n command by abdan (Acolyte) on Jun 30, 2022 at 10:10 UTC
How is usage ? $ ./s2p -e '/^```\w+$/{n; :a N; /\n```$/!ba }' bash: ./s2p: perl: bad interpreter: No such file or directory $ ./s2p bash: ./s2p: perl: bad interpreter: No such file or directory [download] keep such error	[reply] [d/l]
Re^3: Must have CLI of Perl's sed's n command by Anonymous Monk on Jun 30, 2022 at 11:31 UTC
What operating system? Whats the first line of s2p? Why are you calling ./s2p instead of s2p, how did you install it?	[reply]
Re: Must have CLI of Perl's sed's n command by Fletch (Bishop) on Jun 30, 2022 at 02:02 UTC
Your formatting is kind of terrible, but you can check `$.` and skip if the first line (`next if $. == 1`). Another option might be to use the trick of using `-M` and a version to get something to run before the magical while wrapping the `-n` does. Use something like `-M5.010’;scalar <>;’` to have the first line read (and discarded). The cake is a lie. The cake is a lie. The cake is a lie.	[reply] [d/l] [select]
Re^2: Must have CLI of Perl's sed's n command by LanX (Saint) on Jun 30, 2022 at 02:34 UTC
> Your formatting is kind of terrible, yep, that's one way to express it. > skip if the first line `(next if $. == 1)` If that's the goal (???) `$.-1` is false for the first line only, he could `&&` it with the flip-flop's start condition. Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery}	[reply] [d/l] [select]
Re^2: Must have CLI of Perl's sed's n command by abdan (Acolyte) on Jun 30, 2022 at 02:10 UTC
seems we to conclude there's none, as next if $_ == ... is different; costlier & less eff. - i got/knew it in first place	[reply]
Re^3: Must have CLI of Perl's sed's n command by choroba (Cardinal) on Jun 30, 2022 at 05:50 UTC
$_ and $. are not the same thing. Could you show the sed example you're trying to mimic? I'm not sure I understand. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l]
Re: Must have CLI of Perl's sed's n command by haukex (Archbishop) on Jun 30, 2022 at 07:23 UTC
Please show the `sed` script you're trying to replace along with some sample input.	[reply] [d/l]

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