Re^5: referencing slices - love that DWIM

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Re^6: referencing slices - love that DWIM by syphilis (Archbishop) on May 17, 2008 at 13:57 UTC
A list is an ephermeral thing; a transient set of values on the call stack Ok ... so if, as the docs say, `\(@foo)` returns a list, then precisely what does `[\(@foo)]` return ? Is it (something like) "a reference to an array comprising the list returned by `\(@foo)`" ? (What's the correct terminology ?) Cheers, Rob	[reply] [d/l] [select]
Re^7: referencing slices - love that DWIM by Fletch (Bishop) on May 17, 2008 at 19:47 UTC
That's a single scalar value, which is the anonymous array reference containing a list of references to the individual elements of the array `@foo`. Maybe this will clear it up. `use Data::Dumper qw( Dumper ); my @foo = qw( a b c ); my $x = [ \( @foo ) ]; print Dumper( $x ), "\n"; ${ $x->[1] } = 'z'; print join( "\n", @foo ), "\n"; print Dumper( $x ), "\n";` [download] The cake is a lie. The cake is a lie. The cake is a lie.	[reply] [d/l] [select]
Re^6: referencing slices - love that DWIM by DrHyde (Prior) on May 19, 2008 at 09:58 UTC
However, from the point of view of a perl programmer they are as near as damnit the same thing.	[reply]
Re^7: referencing slices - love that DWIM by Fletch (Bishop) on May 19, 2008 at 12:13 UTC
Except for in the edge cases, which is where thinking they are the same thing gets you into trouble: the `\( @array )` vs `\@array` behavior in question here push\|splice\|etc require an actual ARRAY as their first argument, not a LIST a LIST and an ARRAY will behave differently in scalar context (contrast `scalar qw( a b c )` with `scalar @{[ qw( a b c ) ]}`) Those are three that readily come to my pre-morning-caffeine brane, but there's certainly others. Yes in most cases they'll behave the same, but you need to understand that it is a simplification and know where the idea breaks down. Otherwise you'll be unpleasantly surprised after you have to go chasing down squirrelly context induced wonkyness. The cake is a lie. The cake is a lie. The cake is a lie.	[reply] [d/l] [select]