Re: What it mathches`

use re 'debug';

use re 'debug';
$_="abc def";
#$_= qq!"abc def$"!;

if (/"^abc[A\b]def$"/ ){
    print "\ntrue\n";
}
else
{
    print "\nfalse\n";
}
__END__
Compiling REx `"^abc[A\b]def '
size 19 Got 156 bytes for offset annotations.
first at 1
   1: EXACT <">(3)
   3: BOL(4)
   4: EXACT <abc>(6)
   6: ANYOF[\10A](17)
  17: EXACT <def >(19)
  19: END(0)
anchored ""abc" at 0 (checking anchored) minlen 9
Offsets: [19]
        1[1] 0[0] 2[1] 3[3] 0[0] 6[5] 0[0] 0[0] 0[0] 0[0] 0[0] 0[0] 0[
+0] 0[0] 0[0] 0[0] 11[4] 0[0] 15[0]

false
Freeing REx: `"\"^abc[A\\b]def "'
[download]

use re 'debug';
#$_="abc def";
$_= qq!"abc def$"!;

if (/"^abc[A\b]def$"/ ){
    print "\ntrue\n";
}
else
{
    print "\nfalse\n";
}
__END__
Compiling REx `"^abc[A\b]def '
size 19 Got 156 bytes for offset annotations.
first at 1
   1: EXACT <">(3)
   3: BOL(4)
   4: EXACT <abc>(6)
   6: ANYOF[\10A](17)
  17: EXACT <def >(19)
  19: END(0)
anchored ""abc" at 0 (checking anchored) minlen 9
Offsets: [19]
        1[1] 0[0] 2[1] 3[3] 0[0] 6[5] 0[0] 0[0] 0[0] 0[0] 0[0] 0[0] 0[
+0] 0[0] 0[0] 0[0] 11[4] 0[0] 15[0]
Guessing start of match, REx ""^abc[A\b]def " against ""abc def "...
Found anchored substr ""abc" at offset 0...
Guessed: match at offset 0
Matching REx ""^abc[A\b]def " against ""abc def "
  Setting an EVAL scope, savestack=3
   0 <> <"abc def >       |  1:  EXACT <">
   1 <"> <abc def >       |  3:  BOL
                            failed...
Match failed

false
Freeing REx: `"\"^abc[A\\b]def "'
[download]

Comment on Re: What it mathches` Select or Download Code

Replies are listed 'Best First'.
Re^2: What it mathches` by CountZero (Bishop) on Aug 18, 2009 at 04:20 UTC
Did you notice? The Regex didn't even compile correctly: it failed to take into account the (nonsensical) final double quote after the '`$`'. Of course the regex engine has all reasons to stop reading the regex after '`$`' , but one would expect it to give some kind of error such as "garbage found after '`$`'". Forget the above: I missed the 'space' after the 'def'. CountZero A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James	[reply] [d/l] [select]
Re^3: What it mathches` by Anonymous Monk on Aug 18, 2009 at 07:04 UTC
$" is in perlvar `die qq!{$"}!; __END__ { } at - line 2.` [download]	[reply] [d/l]
Re^4: What it mathches` by CountZero (Bishop) on Aug 19, 2009 at 05:59 UTC
You are right. I did miss the "space" after the 'def'. CountZero A program should be light and agile, its subroutines connected like a string of pearls. The spirit and intent of the program should be retained throughout. There should be neither too little or too much, neither needless loops nor useless variables, neither lack of structure nor overwhelming rigidity." - The Tao of Programming, 4.1 - Geoffrey James	[reply]