Re: reverse is not reversing

Print is imposing a list context.

You need scalar context for string reverse

print scalar reverse $test;

What's happening is that the one element list is reversed now, which is of course useless.

  DB<5> print reverse qw/a1 b2 c3/               # inverting list
c3b2a1
  DB<6> print scalar reverse qw/a1 b2 c3/        # inverting string
3c2b1a
[download]

Cheers Rolf
_{(addicted to the Perl Programming Language :)

Wikisyntax for the Monastery
FootballPerl is like chess, only without the dice}

update

added code

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Re^2: reverse is not reversing by badbanana (Novice) on Nov 26, 2018 at 15:17 UTC
oh. it only works with more than one word. i thought it would reverse "apple" into "elppa".	[reply]
Re^3: reverse is not reversing by choroba (Cardinal) on Nov 26, 2018 at 15:21 UTC
No, it will reverse "apple" into "elppa", but only in scalar context. Read more about context in the book Modern Perl. Update: Fixed the book title. Thanx LanX. ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l]
Re^4: reverse is not reversing by LanX (Saint) on Nov 26, 2018 at 15:32 UTC
> in the book Moder Perl Molder Perl? ;-p Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply]
Re^5: reverse is not reversing by tobyink (Canon) on Nov 26, 2018 at 19:12 UTC
Re^6: reverse is not reversing by LanX (Saint) on Nov 26, 2018 at 19:18 UTC
Re^3: reverse is not reversing by LanX (Saint) on Nov 26, 2018 at 15:21 UTC
> it only works with more than one word that's wrong, context matters (LHS) not input (RHS) `DB<9> print reverse "text" # list context text DB<10> print scalar reverse "text" # scalar context txet DB<11> $a= reverse "text" # scalar DB<12> print $a # still print LIST, but $a is +already reversed txet` [download] Cheers Rolf _{(addicted to the Perl Programming Language :) Wikisyntax for the Monastery FootballPerl is like chess, only without the dice}	[reply] [d/l]