The condition at the end running once before the test is something I've long known, since the Pascal days. That for doesn't is not something I've thought about.

$value= "global";

do { print "Inside block: $value\n" }
   for (my $value= 5;  $value < 7;  ++$value);

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does not compile, so whether the loop variable is set first or later or what the scope is is moot. For the list form, 
$_= 1;

do { print "Inside block: $_\n" }
   for (5..7);

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It is intuative that it work the same way, one iteration per item in the list, and you can't use a variable, e.g. 
do { print "Inside block: $value\n" }
   for my $value (5..7);

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doesn't compile either. So variable scope issues are avoided.

Interesting.

—John

In reply to Re: Re: Re: Re: {} vs do{} by John M. Dlugosz
in thread {} vs do{} by John M. Dlugosz

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