Re: oneliner cat like capability

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Re^2: oneliner cat like capability by jwkrahn (Abbot) on Oct 29, 2019 at 20:02 UTC
`perl -pe "" dataoutput.txt` [download] `perl -pe1 dataoutput.txt` [download] :)	[reply] [d/l] [select]
Re^3: oneliner cat like capability by AnomalousMonk (Archbishop) on Oct 30, 2019 at 04:47 UTC
... or `-pe;` (update: but see this!) Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^4: oneliner cat like capability by afoken (Chancellor) on Oct 30, 2019 at 05:42 UTC
... or `-pe;` Works on Windows, doesn't on POSIX-compatible shells (bash and many others). The semicolon is used by the shell, so it won't be passed to perl. POSIX: Shell Command Language: Sequential Lists Commands that are separated by a <semicolon> (`';'`) shall be executed sequentially. The format for executing commands sequentially shall be: `command1 [; command2] ...` [download] Each command shall be expanded and executed in the order specified. Running bash 4 on Linux: `>bash --version GNU bash, version 4.3.48(1)-release (x86_64-slackware-linux-gnu) Copyright (C) 2013 Free Software Foundation, Inc. License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gp +l.html> This is free software; you are free to change and redistribute it. There is NO WARRANTY, to the extent permitted by law. >perl -pe; No code specified for -e. >` [download] Alexander -- Today I will gladly share my knowledge and experience, for there are no sweeter words than "I told you so". ;-)	[reply] [d/l] [select]
Re^2: oneliner cat like capability by gradius85 (Novice) on Oct 29, 2019 at 20:12 UTC
I see what I did wrong or why it works the way I have. However, why is it important to have the 'n' or 'p' before the 'e'? Thank you for the help.	[reply]
Re^3: oneliner cat like capability by AnomalousMonk (Archbishop) on Oct 29, 2019 at 23:33 UTC
... why is it important to have the 'n' or 'p' before the 'e'? Per perlrun, the `-e` switch expects source text to follow, either with or without a space. The switch sequence `-en` means that Perl is trying to execute `"n"`. The effect of this is made more clear with strictures enabled (see strict): `c:\@Work\Perl\monks>perl -wMstrict -en "print" foo get_bar() Bareword "n" not allowed while "strict subs" in use at -e line 1. Execution of -e aborted due to compilation errors. c:\@Work\Perl\monks>perl -wMstrict -ep foo get_bar() Bareword "p" not allowed while "strict subs" in use at -e line 1. Execution of -e aborted due to compilation errors.` [download] Update: See jwkrahn's example here of `-pe1` which gives `-e` the source 1 (that's a digit 1) to evaluate within the source code framework established by the `-p` switch. Give a man a fish: `<%-{-{-{-<`	[reply] [d/l] [select]
Re^3: oneliner cat like capability by choroba (Cardinal) on Oct 29, 2019 at 21:09 UTC
It's not important. You can write the loop yourself: `perl -e 'print while <>' -- dataoutput.txt` [download] It's just helpful: if you want to iterate over the input and print always, use -p; if you want to iterate but not print, use -n; otherwise, use neither. `map{substr$_->[0],$_->[1]\|\|0,1}[\\|\|{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^ARGV,3]`	[reply] [d/l] [select]