CODEWITHSUNDEEP
perlcommand-line
Charlie Frank
Charlie Frank

Reputation: 76

perl command line equivalent of php -E

php -R '$count++' -E 'print "$count\n";' < somefile

will print the number of lines in 'somefile' (not that I would actually do this).

I'm looking to emulate the -E switch in a perl command. 

perl -ne '$count++' -???? 'print "$count\n"' somefile

Is it possible?

Upvotes: 2

Views: 227

Answers (3)

TLP
TLP

Reputation: 67900

TIMTOWTDI

You can use the Eskimo Kiss operator:

perl -nwE '}{ say $.' somefile

This operator is less magical than one thinks, as seen if we deparse the one-liner:

$ perl -MO=Deparse -nwE '}{say $.' somefile 
BEGIN { $^W = 1; }
BEGIN {
    $^H{'feature_unicode'} = q(1);
    $^H{'feature_say'} = q(1);
    $^H{'feature_state'} = q(1);
    $^H{'feature_switch'} = q(1);
}
LINE: while (defined($_ = <ARGV>)) {
    ();
}
{
    say $.;
}
-e syntax OK

It simply tacks on an extra set of curly braces, making the following code wind up outside the implicit while loop.

Or you can check for end of file.

perl -nwE 'eof and say $.' somefile

With multiple files, you get a cumulative sum printed for each of them. 

perl -nwE 'eof and say $.' somefile somefile somefile
10
20
30

You can close the file handle to get a non-cumulative count:

perl -nwE 'if (eof) { say $.; close ARGV }' somefile somefile somefile
10
10
10

Upvotes: 10

Sebastian Paaske T&#248;rholm
Sebastian Paaske T&#248;rholm

Reputation: 50858

You can use an END { ... } block to add code that should be executed after the loop:

perl -ne '$count++; END { print "$count\n"; }' somefile

You can also easily put it in its own -e argument, if you want it more separated:

perl -ne '$count++;' -e 'END { print "$count\n"; }' somefile

See also:

Upvotes: 6

Sebastian Stumpf
Sebastian Stumpf

Reputation: 2791

This should be what you're looking for:

perl -nle 'END { print $. }'  notes.txt

Upvotes: 6

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