If you wanted to do this with map, here is one such approach. Note that I'm using "$i,$j,$k" -- I think it's a bad idea to use "$a" and "$b" as names for application data variables, because in Perl these names are used by the "sort" function. 
my ($i, $j, $k) = (2, 0, 4);  # make up some data values

my $ltr = "i";
my $combined = join "", map { $_ &&= "$ltr=$_ "; $ltr++; ($_)? $_:"" }
+ ( $i, $j, $k );

print $combined, "\n";

[download]
But frankly, I would prefer to use a solution that puts the values into a hash and loops over the sorted hash keys, as suggested by some of the replies above. (That way, you can safely start at "a" if you want.)

In reply to Re: Scalar joining, concatenation, involving varying text by graff
in thread Scalar joining, concatenation, involving varying text by mhearse

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