Re: The best way to replace several fragments of the file starting with the one pattern(marker) and ending with another pattern/marker.

Yet another way to do it. I believe Perl 5.10 is only needed because of the state variable. If it were moved above the loop and made into a my variable, an earlier Perl should work. I also moved the informational output to STDERR.

#!/usr/bin/env perl

use 5.010;

use strict;
use warnings;

my %marker = (
    "AAAAAA\n" => {
        end     => "BBBBBB\n",
        repl    => <<'EOD',
f11
f12
f13
EOD
    },
    "CCCCCC\n" => {
        end     => "DDDDDD\n",
        repl     => <<'EOD',
f21
f22
EOD
    },
);

while ( <DATA> ) {
    state $section;
    warn "$. $_";
    if ( $section ) {
        if ( $_ eq $section->{end} ) {
            warn "========= End of the fragment detected at $.\n";
            print $section->{repl};
            $section = undef;
        }
    } elsif ( $section = $marker{$_} ) {
        warn "========= Start of the fragment detacted at $.\n";
    } else {
        print;
    }
}

__DATA__
aaa
aaa
AAAAAA
ccc
ddd
BBBBBB
111
222
333
CCCCCC
444
555
666
DDDDDD
777
888
999
[download]

Comment on Re: The best way to replace several fragments of the file starting with the one pattern(marker) and ending with another pattern/marker. Select or Download Code

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Re^2: The best way to replace several fragments of the file starting with the one pattern(marker) and ending with another pattern/marker. by likbez (Sexton) on Nov 01, 2020 at 16:15 UTC
This looks like a solution based on ingenious emulation of Perl range operator with the advantage that it can accommodate multiple fragments. Like in Perl range operator there is a variable this is true within the range and false outside. Thank you ! Here is a slightly modified variant that I used for testing: [0] # cat test_range2 #!/usr/bin/env perl use 5.010; use strict; use warnings; my $debug=0; my %marker = ( "AAAAAA\n" => { end => "BBBBBB\n", repl => <<'EOD', f11 f12 f13 EOD }, "CCCCCC\n" => { end => "DDDDDD\n", repl => <<'EOD', f21 f22 EOD }, ); state $section; while ( <DATA> ) { ($debug) && warn "$. $_"; if ( $section ) { if ( $_ eq $section->{end} ) { ($debug) && warn "========= End of the fragment detected a +t $.\n"; print $section->{repl}; $section = undef; print; } } elsif ( $section = $marker{$_} ) { ($debug) && warn "========= Start of the fragment detacted at +$.\n"; print; # print marker }else{ print; } } __DATA__ aaa aaa AAAAAA ccc ddd BBBBBB 111 222 333 CCCCCC 444 555 666 DDDDDD 777 888 999 [download] That produces: [0] # perl test_range2 aaa aaa AAAAAA f11 f12 f13 BBBBBB 111 222 333 CCCCCC f21 f22 DDDDDD 777 888 999	[reply] [d/l]

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Re^2: The best way to replace several fragments of the file starting with the one pattern(marker) and ending with another pattern/marker.
by likbez (Sexton) on Nov 01, 2020 at 16:15 UTC

This looks like a solution based on ingenious emulation of Perl range operator with the advantage that it can accommodate multiple fragments.

Like in Perl range operator there is a variable this is true within the range and false outside.

Thank you !

Here is a slightly modified variant that I used for testing:

[0]  # cat  test_range2
#!/usr/bin/env perl

use 5.010;

use strict;
use warnings;
my $debug=0;
my %marker = (
    "AAAAAA\n" => {
        end     => "BBBBBB\n",
        repl    => <<'EOD',
f11
f12
f13
EOD
    },
    "CCCCCC\n" => {
        end     => "DDDDDD\n",
        repl     => <<'EOD',
f21
f22
EOD
    },
);

state $section;
while ( <DATA> ) {
    ($debug) && warn "$. $_";
    if ( $section ) {
        if ( $_ eq $section->{end} ) {
            ($debug) && warn "========= End of the fragment detected a
+t $.\n";
            print $section->{repl};
            $section = undef;
            print;
        }
    } elsif ( $section = $marker{$_} ) {
        ($debug) && warn "========= Start of the fragment detacted at 
+$.\n";
        print; # print marker
    }else{
      print;
    }

}

__DATA__
aaa
aaa
AAAAAA
ccc
ddd
BBBBBB
111
222
333
CCCCCC
444
555
666
DDDDDD
777
888
999
[download]

[0]  # perl  test_range2
aaa
aaa
AAAAAA
f11
f12
f13
BBBBBB
111
222
333
CCCCCC
f21
f22
DDDDDD
777
888
999

[reply]
[d/l]