perl - Printing an array within double quotes

Question

my @a = (1,2,3,4,5);

print @a;      #output: 12345

print "
";

print "@a";    #output: 1 2 3 4 5

Printing an array by putting its name withing double quotes puts a space between each index's value at output. How does it do it? Why doesn't print @a; prints the same? What's the need of both types? I mean when will you use print @a; instead of print "@a"; and vice versa.

Answer 1

When an array is interpolated in a string, the assumption is you may want to be able to visually distinguish elements; when you print a list, the assumption is you just want that data output contiguously. Both are configurable; $, (default '') is inserted between elements of a list being printed, while $" (default ' ') is inserted between elements of an array interpolated into a string.