One approach is to use a regular expression: 
#!/usr/bin/perl
use common::sense;
my $data = join('', <DATA>);
$data =~ s{(^|\n)begin\n         # begin at start of string or line
          (.*?\n)*?              # lines to skip (non-greedy)
          end\n}                 # matching end
         {$1begin\nend\n}sx;
print $data;
__DATA__
a
begin
1
a
2
end
c
begin
c
end
a
begin
1

[download]
Update: added \n anchors and commented the regexp.

In reply to Re: how to cut context between first "begin" and "end"? by snoopy
in thread how to cut context between first "begin" and "end"? by cxfcxf

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