Re: Mysteries of unpack("a", ...)

which indicates that I don't know what the floop unpack("a4") does.

substr($_, 0, 4)
[download]

or rather

substr(do { _utf8_off(my $internal = $_); $internal }, 0, 4)
[download]

Comment on Re: Mysteries of unpack("a", ...) Select or Download Code

Replies are listed 'Best First'.
Re^2: Mysteries of unpack("a", ...) by BrowserUk (Patriarch) on Jan 03, 2009 at 06:45 UTC
Or rather `substr substr(do { _utf8_off(my $internal = $_); $internal }, 0, 4) . chr(0) x 4, 0, 4;` [download] How's that! (for out-pedanting the pedant! (Always assuming I got it right :) From perlfunc:pack (I'm too tired to fix up the link): a A string with arbitrary binary data, will be null padded. Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. "Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."	[reply] [d/l]
Re^3: Mysteries of unpack("a", ...) by ikegami (Patriarch) on Jan 03, 2009 at 06:58 UTC
That's wrong. While `pack` (whose documentation you quoted) will add NULs, `unpack` doesn't. `>perl -le"print length unpack 'a4', ''" 0` [download] If anything, `unpack` should do the opposite (remove trailing NULs), but it doesn't do that either. `>perl -le"print length unpack 'a4', qq{\0\0\0\0}" 4` [download]	[reply] [d/l] [select]