Perl regex can't find match-CodePudding

So I'm working on my own little formatting correction script that uses Perl regex for substitution, but I can't get this one to match. I've used similar matching for other fixes but this one doesn't work and I can't figure out why.

# basically takes in a string to modify and the match and substitution strings
perlRegex(){
  PERL_BADLANG=0 perl -le '
  $string = '"'"''"${1}"''"'"';
  $string =~ s/'"${2}"'/'"${3}"'/gm;
  print "$string\n";
  exit';
}

LINE_BREAK='\n'

# contents is the example below
EDITED=$(cat file.txt);
EDITED=$(perlRegex "${EDITED}" '(?<='"${LINE_BREAK}"')(  )([^{] {$'"${LINE_BREAK}"')([^\s][^;] ;$)' '$1$2$1$1$3')

My current attempt is https://regex101.com/r/vgatOd/1 which gives me the output I want.

(?<=\n)( )([^{] {$\n)([^\s][^;] ;$) to $1$2$1$1$3

(?<=\n)( ) $1: copies the spaces at the beginning of the line

([^{] {$\n) $2: captures the remaining content of the line with ending {

([^\s][^;] ;$) $3: captures the next line without a leading spaces, with ending ;

The substitution will add the spaces twice on before the second line.

Example input:


    if (debug) {
Tools.DebugLine("Log");
    }

Aim is to pad the Tools line to be at the correct column:


    if (debug) {
        Tools.DebugLine("Log");
    }

Given the regex101 does what I would like it to do, I'm perplexed as to what part of it does not work in Perl regex.

CodePudding user response：

Solved by changing to just using \n instead of $ along with them

https://regex101.com/r/poQlwm/1

(?<=\n)([ ] )([^{] \{\n)([^\s][^;] ;\n)

CodePudding user response：

Taken approach to make java file formatting isn't error prone, you should consider a better way to achieve the desired effect.

The chosen regular expression is quite excessive and mixes \n, , \s all of which falls under \s class.

The following demo code strips regular expression for simplification.

use strict;
use warnings;

my $data = do { local $/; <DATA> };
my $re = qr/([^\n] ?\{\s )(\S ?;)(\s \})/;
my $indent = ' ' x 8;

$data =~ s/$re/$1${indent}$2$3/gsm;

print $data;

__DATA__
    if (debug) {
Tools.DebugLine("Log");
    }

Output

    if (debug) {
        Tools.DebugLine("Log");
    }

Please see Perl regular expressions