More about arrayref/hashref in spectest suite
Patrick R. Michaud
the spectest suite. S02-literals/autoref.t:59 has the
following:
# Implicit referentiation of arrays in assignment to an array element
{
my @array = <a b c>;
my @other;
@other[1] = @array;
is ~@other, " a b c", '@other[$idx] = @array works (1)';
is +@other, 2, '@other[$idx] = @array works (2)';
is +@other[1], 3, '@other[$idx] = @array works (3)';
}
The idea given by the test appears to be that the
C< @other[1] = @array; > statement causes @other[1] to
contain a reference to @array. After the statement, @other
contains two elements, the second of which is an array of three
elements.
However, S03 and STD.pm seem to indicate that having @other[1]
on the left would result in a list assignment, not an item
assignment. As a list assignment, @other[1] would then get
the first element from @array, and we'd get a warning about
the leftover elements.
By way of illustration, contrast the two assignments at
the end of the following code:
my @x = <a b>;
my @y;
@y[1] = @x, 'c';
@y[1,2,3] = @x, 'c';
The second assignment would seem to clearly be a list
assignment, leaving @y with (undef, 'a', 'b', 'c').
But is the first assignment parsed as an item assignment or
a list assignment? If it is parsed as an item assignment,
how does the parser recognize it as such? If it's parsed
as a list assignment, then should we be creating an
Array reference here or merely assigning elements to
the container on the left?
Or am I missing something else altogether?
Thanks in advance for any answers,
Pm