Re^4: Avoiding if/else knots II

As for your example, what good is it to use a labelled loop for a list containing one variable? ;-)

That's easy.

The label is there to show that the block is emulating as a SWITCH statement.
The label is also there to show what the last statements refer to.
the for with just one variable is simply there to assign $value to $_ without explicitly doing it

it's also there to keep the original content of $_ outside the SWITCH ("loop"). Try this

my $v="V";
$_="_";
for ( $v ) {
    print "inside: $_\n";
}
print "outside: $_\n";
[download]

s$$([},&%#}/&/]+}%&{})*;#$&&s&&$^X.($'^"%]=\&(|?*{%
+.+=%;.#_}\&"^"-+%*).}%:##%}={~=~:.")&e&&s""`$''`"e

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Re^5: Avoiding if/else knots II by shmem (Chancellor) on Aug 30, 2006 at 12:44 UTC
It looks good ;-) (to me). I read this as "switch for value ..." Ah, style. Still, I deem it a misuse of `for`. It sets up the context of a loop whilst none needed. This one looks better (for me, that is :-) `# SWITCH { local $_ = $MyValue; /$reg2/ && do { sub_for_key_a(); last; }; /$reg1/ && do { whatever(); sub_for_key_b(); last; }; #default sub_for_default(); } # END SWITCH` [download] since a bare block does the job and is less clutter. And I also read it as "switch for $MyValue" ;-) --shmem _($_=" "x(1<<5)."?\n".q·/)Oo. G°\ / /\_¯/(q / ---------------------------- \__(m.====·.(_("always off the crowd"))."· ");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}	[reply] [d/l] [select]
Re^6: Avoiding if/else knots II by Skeeve (Parson) on Aug 30, 2006 at 20:17 UTC
It wasn't my idea. I took it from "Programming Perl" by Wall, Christiansen & Schwartz. Chapter 2: You might think it odd to write a loop over a single value, but a common idiom for a switch statement is to use foreach's aliasing capability to make a temporary assignment to $_ for convenient matching. `s$$([},&%#}/&/]+}%&{});#$&&s&&$^X.($'^"%]=\&(\|?{%` `+`.+=%;.#_}\&"^"-+%*).}%:##%}={~=~:.")&e&&s""`$''`"e	[reply] [d/l] [select]