It is worth noting, however, that, contrary to map, grep evaluates its second argument in scalar context:
And contrary to grep and map, foreach evaluates its body in void context: 
$ perl
sub ctx { print wantarray ? "list" : defined wantarray ? "scalar" : "v
+oid" }
@x = (1);
print "map:";
map ctx, @x;
print "\ngrep:";
grep ctx, @x;
print "\nfor:";
ctx for @x;
__END__
map:list
grep:scalar
for:void

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In reply to Re: Unhappy returns by ysth
in thread Unhappy returns by tlm

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