Re^4: Reliable way to detect base64 encoded strings

Regex are not my favorite part of Perl....even if they are powerful. I'm trying to use your way to detect if a string is base64...so I was taking what you had and putting an if around it. I'm sure I'm just not getting it....could you give me some pointers?

if($string_whole =~ m 
/
    ^ 
    (?: [A-Za-z0-9+/]{4} )*
    (?: [A-Za-z0-9+/]{2} [AEIMQUYcgkosw048] = 
    |   [A-Za-z0-9+/] [AQgw] ==
    )?
    \z
/x
) $&Log ("it found base64-$i");
[download]

Thanks in advance for your expertise.

Comment on Re^4: Reliable way to detect base64 encoded strings Download Code

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Re^5: Reliable way to detect base64 encoded strings by ikegami (Patriarch) on Apr 16, 2010 at 05:05 UTC
You have the right idea, but `if (...) $&Log ("it found base64-$i");` [download] is not valid Perl. You want `if($string_whole =~ m/ ^ (?: [A-Za-z0-9+/]{4} )* (?: [A-Za-z0-9+/]{2} [AEIMQUYcgkosw048] = \| [A-Za-z0-9+/] [AQgw] == )? \z /x) { Log("$string_whole is valid base64"); }` [download]	[reply] [d/l] [select]
Re^6: Reliable way to detect base64 encoded strings by hahngoldn (Initiate) on Apr 16, 2010 at 22:49 UTC
when I use it as you have it I get `Unmatched [ in regex; marked by <-- HERE in m/ ^ (?: [ <-- HERE A-Za-z0-9+/ at C:\aaa\aeh_pop.pl line 153.` [download] I thought I was getting a problem with the regex...not the IF....but I didn't copy this in because i figured it was something I was doing. I see matched brackets... I tried to pull up into one line thinking the white space was giving issues...that didn't help. Thanks.	[reply] [d/l]
Re^7: Reliable way to detect base64 encoded strings by ikegami (Patriarch) on Apr 17, 2010 at 04:23 UTC
Oops, mine wasn't valid Perl either! I used an unescape "/" in the pattern. Two solutions: escape it, or change the delimiter. I corrected the original post.	[reply]
Re^8: Reliable way to detect base64 encoded strings by Anonymous Monk on Apr 30, 2010 at 19:10 UTC
Re^9: Reliable way to detect base64 encoded strings by ikegami (Patriarch) on Apr 30, 2010 at 21:03 UTC