While working on an algorithm for finding polynomials to fit a bunch of points (which you can see on my scratchpad), I tripped across this little syntax quirk and wondered this behavior is expected, or possibly a bug in my perl (version 5.8.7, the stock cygwin build).

Namely, I found that this code:

use strict;
my $a = [ qw(mary had a little lamb with mint jelly) ];
my $b = [ $a->[1..4] ];
my $c = [ @{$a}[1..4] ];

print "a is [ @$a ]\n";
print "b is [ @$b ]\n";
print "c is [ @$c ]\n";
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a is [ mary had a little lamb with mint jelly ]
b is [ mary ]
c is [ had a little lamb ]
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That is, $b is equal to [ $a->[0] ]. I cannot imagine how perl's syntax rules got there. Apparently, 1..4 is being evaluated in scalar context (despite the expression $a->[1..4] clearly being evaluated in a list context), and the result of scalar(1..4) is numerically equal to 0. This struck me as bizarre; I would have thought scalar(1..4) would be 4, not ''.

Is anyone else startled by this behavior?

@/=map{[/./g]}qw/.h_nJ Xapou cets krht ele_ r_ra/;
map{y/X_/\n /;print}map{pop@$_}@/for@/
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