I don't know if this is the "least resource-intensive" method, but it does seem to do what you requested. Please note that blank lines are not added to the array. 

use strict;

#-- Change the end of record character to read the whole file.
undef $/;

#-- Create the array
my @ary = split (/\s+/,<DATA>);
print join(" / ", @ary);

__DATA__
boop noop boop crep
a1 a2 a3 a4 a5
b1 b2
c1 c2 c3 c4

d1 d2 d3

[download]

Is this what you wanted?

In reply to How about this? by Rhose
in thread Getting data out of __DATA__ and __END__ by George_Sherston

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