While I have no inclination to quarrel with FloydATC's code, his statement in para 1 may be misleading (I, for one, find it easier to type 3 letters rather than seven).

In fact, while some programmers use for and foreach differently, they are indistinguishable except for the spelling ...and either can be used in a C-style loop or a Perlish version with or without an explicit iterator:

C:\>perl -E "my @arr=qw(a b c d); my $a; for $a(@arr) {say $a;}"
a
b
c
d

<c>C:\>perl -E "my @arr=qw(a b c d); my $a; foreach $a(@arr) {say $a;}
+"
a
b
c
d

[download]

And here's brian d foy's response to a question on SO ( http://stackoverflow.com/questions/2279471/whats-the-difference-between-for-and-foreach-in-perl ) back in 2010:

"They used to be separate ideas, but now they are synonyms. Perl figures out what to do based on what's in the ( ) instead of using the keyword. Blame the people who couldn't type an extra four characters. :)
C:\>perl -e "foreach ($i=0;$i<10;$i++) { print $i }" # NB: '-e' & 'pri
+nt'
0123456789

[download]

And though foy's statement doesn't offer a version or date when "used to be separate ideas" changed, nodes here in the Monastery, back at least as far as 2000, disagree -- some globally, and some only with respect to Perl 4 vs. Perl 5.

Just for completeness or merely to be excessively didactic :-), if one changes foy's (5.8?) code to my (5.18) "for" ...

C:>perl -E "for ($i=0;$i<10;$i++) { say $i }" # Irrelevant differences
+ '-E' & 'say'
0
1
2
3
4
5
6
7
8
9

[download]


Come, let us reason together: Spirit of the Monastery
-->

In reply to Re^2: looping in 2d array by ww
in thread looping in 2d array by Linguist

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