使用 Perl 打印整个字符串，直到出现子字符串匹配

Question

I am looking for a quick fix for this, as I don't really specialise in perl/regex.

I have a string as follows ;

abc_def0_ghi4_jkl_mno_pqr_123456.log some_extra_messages and random garbage

and I want a small perl script (not one-liner command) that will search for the .log file name, as well as remove the numbers at the end of the file. So that the output looks like

abc_def0_ghi4_jkl_mno_pqr

Any suggestions?

Answer 1

A quick (and maybe dirty) answer based on the few information you provided:

use strict;
use warnings;

my $str = "abc_def0_ghi4_jkl_mno_pqr_123456.log some_extra_messages and random garbage";

my ($name) = ( $str =~ /^(\w+)_\d+\.log/);
print $name, "\n";

This assumes that the name is located at the beginning of the script and contains only word characters (letters, numbers, underscore). It will capture everything until it reaches a sequence of numbers preceded by an underscore and followed by .log .

Answer 2

It looks like you want to output everything up to, but not including, the underscore before the log file name. Is that correct? You need to be very specific about how the data is structured; otherwise, we are having to guess.

Here's a short script that takes your example input and produces your example output:

use strict;
use warnings;

my $str = 'abc_def0_ghi4_jkl_mno_pqr_123456.log some_extra_messages and random garbage';

s/_[^_]+\.log.*// for $str;

print $str, "\n";

The s/_[^_]+\\.log.*// substitution matches:

• an underscore
• followed by one or more non-underscores
• followed by the characters .log
• followed by any additional characters to the end of line

The matched text is replaced with an empty string (deleted), and the remaining text is printed.