heredoc and Carriage return

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

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Re: heredoc and carriers return by choroba (Cardinal) on Oct 25, 2016 at 09:35 UTC
I can confirm the behaviour in 5.25.5 (built on September 16) on Linux. `#!/usr/bin/perl use warnings; use strict; use feature qw{ say }; my $nix = << '__NIX__'; line 1 line 2 __NIX__ my $win = << '__WIN__'; # ^M present at end of lines. line 1 line 2 __WIN__ # ^M present here, too: my $quoted = 'line1 line2 '; say /\r/ for $nix, $win, $quoted;` [download] I can't find it documented anywhere. Update: It doesn't work for normal quoted strings, either. ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l] [select]
Re^2: heredoc and carriers return by LanX (Saint) on Oct 25, 2016 at 09:43 UTC
I suppose it's related to Perl being OS agnostic regarding \n when printing. Please check the hex code of the here doc to see what is really embedded. Edit: OK seems like the regex is supposed to do this. Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :) Je suis Charlie!}	[reply]
Re^2: heredoc and carriers return by LanX (Saint) on Oct 25, 2016 at 11:10 UTC
> I can't find it documented anywhere I'm to busy now, but you might wanna look into `open` which mentions a IO layer called `:crlf` or `encoding` or other docs mentioned in the footnotes ... Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :) Je suis Charlie!}	[reply] [d/l]
Re^3: heredoc and carriers return by choroba (Cardinal) on Oct 25, 2016 at 12:15 UTC
Neither open nor encoding describe how they influence Perl's parsing of multiline string literals. ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l]
Re: heredoc and carriers return by shawnhcorey (Friar) on Oct 25, 2016 at 11:09 UTC
Try: `my $win = << "__WIN__"; line 1\r line 2\r __WIN__` [download] Using a double quote around the heredoc tag will cause the heredoc to be interpolated. That is, the "\r" will be interpolated as a CR (U+000D).	[reply] [d/l]
Re: heredoc and carriers return by LanX (Saint) on Oct 25, 2016 at 13:47 UTC
> heredoc read the LF ( \n ) , but dont parse / stores the carriers return ( \r ) there is a misconception on your side and probably it's an XY Problem too. \n is the newline according to the OS you use and NOT (only) the LF from ASCII. When you `print "some line break \n and more lines"` then Perl will autotranslate the \n to whatever *nix, win or mac wants to see. Perl does it to assure maximum OS independency. You are probably bitten by the reverse effect, that some combinations of CR and LF are interpreted as \n. The answer to your problem is asking what for do you need it? If you just need linebreaks ignore the effect, if you need the \r otherwise, do like suggested and include them explicitly. You are free to put the text into an external file and read it in `binmode` , or even encode it as hex or base64 if you really need literally the same ascii code. Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :) Je suis Charlie!}	[reply] [d/l]
Re^2: heredoc and carriers return by gabrielsousa (Sexton) on Oct 25, 2016 at 14:42 UTC
i have a pdf file / binary inside my perl script using heredoc has 40 Carriage returns, i can search on VI, i see the ^M but when i print to a file i lose all Carriage returns.. i'm assuming is a problem of heredoc	[reply]
Re^3: heredoc and carriers return by LanX (Saint) on Oct 25, 2016 at 16:53 UTC
Heredocs are not meant for binary data. If you don't want to read from an external file, then I can only see two options try to put it after DATA and read from there (not tested) encode and decode the stuff in an ASCII format, like base64 HTH ! :) Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :) Je suis Charlie!}	[reply]
Re^4: heredoc and carriers return by gabrielsousa (Sexton) on Oct 25, 2016 at 20:08 UTC
Re^4: heredoc and carriers return by gabrielsousa (Sexton) on Oct 25, 2016 at 22:11 UTC
Re^5: heredoc and carriers return by pryrt (Abbot) on Oct 25, 2016 at 23:24 UTC
Some notes below your chosen depth have not been shown here
Re: heredoc and Carriage return by choroba (Cardinal) on Oct 25, 2016 at 20:38 UTC
Crossposted to reddit. Please, next time link to your crosspost yourself, to avoid duplicate effort by people not attending both sites. ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l]
Re^2: heredoc and Carriage return by LanX (Saint) on Oct 25, 2016 at 21:35 UTC
> to avoid duplicate effort by people not attending both sites Indeed! :/ Cheers Rolf _{(addicted to the Perl Programming Language and ☆☆☆☆ :) Je suis Charlie!}	[reply]