equivalent perl for sed command ..newbie question

[walter]

Hi,

I just started learning perl.

Now I know

perl -p -e 's/exp1/exp2/g' file

is equivalent to

sed -e 's/exp1/exp2/g' file

But I can't realize what's the perl equivalent to

sed -e '/exp1/,/exp2/d' file

I tried to mimic it using

perl -p -e '/exp1/,/exp2/d'

but, of course, it didn't work...

Yes...I know it's a dumb question....Sorry!

Thanks for your time and patience !

 

[Ben Morrow]

Now I know

perl -p -e 's/exp1/exp2/g' file

is equivalent to

sed -e 's/exp1/exp2/g' file

Except that Perl's regexes are better

But I can't realize what's the perl equivalent to

sed -e '/exp1/,/exp2/d' file

perl -ne'print unless /exp1/.../exp2/'

See perldoc perlop for .. and ..., and the differences between them.

Ben

 

[Anno Siegel]

Except that Perl's regexes are better


perl -ne'print unless /exp1/.../exp2/'

See perldoc perlop for .. and ..., and the differences between them.

Alternatively, use the program s2p, which comes with the Perl distribution.
It translates sed scripts to Perl scripts. In this case it comes up with
a whole lot of code for what can apparently be done in a single line, but
it does so automatically.

Anno

 

[Glenn Jackman]

perl -ne'print unless /exp1/.../exp2/'

See perldoc perlop for .. and ..., and the differences between them.

Ah, the lightbulb illuminates. Thanks for that example: I now
understand the .. operator in a scalar context. Still a bit fuzzy on
the difference with ... though. Can someone provide another example?
This outputs the same results whether I use .. or ...:

#!/usr/local/bin/perl -w
use strict;
while (<DATA>) {
print if /4/../7/;
}
__DATA__
1
2
3
4
5
6
7
8
9

 

[Ben Morrow]

Ah, the lightbulb illuminates. Thanks for that example: I now
understand the .. operator in a scalar context. Still a bit fuzzy on
the difference with ... though. Can someone provide another example?
This outputs the same results whether I use .. or ...:

<snip>

~% echo "12345467" | perl -lne'BEGIN{$/=\1}; print if /4/.../4/'
4
5
4
~% echo "12345467" | perl -lne'BEGIN{$/=\1}; print if /4/../4/'
4
4
~%

Note that the ... example goes off-on-off whereas the .. example goes
off-onoff-onoff.

Ben