[perl #35877] \n after $ in regex (was: Strange regex failure?)

On Thu May 19 03:49:55 2005, shay wrote:
> 
> I believe that the following program should print "OK" 5 times over,
>    but
> it prints "NOT OK" for the first line.
> 


#!/usr/bin/perl

print qq[>10\n] =~ />\d+$ \n/ix  ? "OK\n" : "NOT OK\n";
print qq[>1\n]  =~ />\d+$ \n/ix  ? "OK\n" : "NOT OK\n";
print qq[>10\n] =~ /\d+$ \n/ix   ? "OK\n" : "NOT OK\n";
print qq[>10\n] =~ />\d\d$ \n/ix ? "OK\n" : "NOT OK\n";
print qq[>10\n] =~ />\d+$ \n/x   ? "OK\n" : "NOT OK\n";

__END__

5.8.8:

NOT OK
OK
OK
OK
OK

5.10/blead:
OK
OK
OK
OK
OK


While checking if a test for it exists/while writing one I decied to 
check if the /x was needed:


#!/usr/bin/perl

print qq[>10\n] =~ />\d+$\n/i  ? "OK\n" : "NOT OK\n";
print qq[>1\n]  =~ />\d+$\n/i  ? "OK\n" : "NOT OK\n";
print qq[>10\n] =~ /\d+$\n/i   ? "OK\n" : "NOT OK\n";
print qq[>10\n] =~ />\d\d$\n/i ? "OK\n" : "NOT OK\n";
print qq[>10\n] =~ />\d+$\n/   ? "OK\n" : "NOT OK\n";


__END__
Output:

NOT OK
NOT OK
NOT OK
NOT OK
NOT OK


Is this intended/expected behaviour?

"a\n" =~ m/a$ \n/x; # true
"a\n" =~ m/a$\n/x;  # false
"a\n" =~ m/a$\n/;   # false


Kind regards,

Bram

• [perl #35877] \n after $ in regex (was: Strange regex failure?) by Bram via RT
• Re: [perl #35877] \n after $ in regex (was: Strange regex failure?) by Zefram
• Re: [perl #35877] \n after $ in regex (was: Strange regex failure?) by David Nicol
• Re: [perl #35877] \n after $ in regex (was: Strange regexfailure?) by Bram
• Re: [perl #35877] \n after $ in regex (was: Strange regex failure?) by Yitzchak Scott-Thoennes
• [PATCH] Unintented interpolation of $/ in regex (was: Re: [perl#35877] \n after $ in regex (was: Strange regex failure?)) by Bram
• Re: [PATCH] Unintented interpolation of $/ in regex (was: Re: [perl #35877] \n after $ in regex (was: Strange regex failure?)) by Rafael Garcia-Suarez
• Re: [perl #35877] \n after $ in regex by David Landgren