Array interpolation in Rakudo

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

Shouldn't arrays be interpolated in print/say statements.

In Perl 5 ..


use strict;
use warnings;

my @array = ( 1 , 2 , 3 , 4 );
print "The array is @array";

perl ../../programs/array_interpolation.pl 
The array is 1 2 3 4
[download]

In Perl 6 and rakudo ..

use v6;

my @array = ( 1 , 2 , 3 , 4 );
say "The array is @array";

./perl6 ../../programs/array_interpolationp6.pl 
The array is @array
[download]

Bug? Or wrong understanding on my part?

Comment on Array interpolation in Rakudo Select or Download Code

Replies are listed 'Best First'.
Re: Array interpolation in Rakudo by moritz (Cardinal) on Aug 10, 2010 at 08:21 UTC
The language has changed in that respect - arrays and hashes only interpolate into double-quoted strings if they end in a postcircumfix, that is any bracketing characters coming after an expression. `say "array: @array"; # interpolates nothing say "array: @array[]"; # interpolate all elements say "array: @array[1]"; # interpolate one element say "array: @array.sort"; # no interpolation, does not # end with something brackety say "array: @array.sort()"; # interpolates sorted array` [download] Rakudo implements those cases according to the specification. See also: strings, arrays, hashes, S02: Literals (scroll down) Perl 6 - links to (nearly) everything that is Perl 6.	[reply] [d/l]
Re: Array interpolation in Rakudo by Utilitarian (Vicar) on Aug 10, 2010 at 08:37 UTC
At the moment Using Perl 6 in the section on interpolation has this to say `TODO: explain (non-)interpolation of arrays and hashes once Rakudo gets that right` [download] You are seeing the expected behaviour rather than a bug: You may see a bug if you attempt, (haven't got access to Rakudo @ work) `my @array = ( 1 , 2 , 3 , 4 ); say "The array is {@array}";` [download] The `{}` curly braces within double quotes should allow any expression to be interpolated into the string. `print "Good ",qw(night morning afternoon evening)[(localtime)[2]/6]," fellow monks."`	[reply] [d/l] [select]
Re^2: Array interpolation in Rakudo by moritz (Cardinal) on Aug 10, 2010 at 09:06 UTC
The latest version of "Using Perl 6" has a bit more to say about interpolation, though I still wasn't happy with it. I hope this commits makes things clearer. Perl 6 - links to (nearly) everything that is Perl 6.	[reply]