Re: [perl #130038] Builtin variable for loop index in foreach

On Tue, Nov 08, 2016 at 10:35:07AM +0000, Ed Avis wrote:
> Dave Mitchell wrote:
> 
> >For ranges, e.g. (1..10) and ('a'..'z'), it only records the current value and the last value.
> 
> But for numeric ranges, if you know the current value it is just a subtraction to find its index.

No, at the point where you have iterated  'for (11..20) {}' say, 7 times,
exactly two values are currently stored: 17 and 20. There is no way (in
general) to deduce that value '7' from that. Extra bookkeeping of one form
or another would need to be added.

-- 
A walk of a thousand miles begins with a single step...
then continues for another 1,999,999 or so.

• [perl #130038] Builtin variable for loop index in foreach by Ed Avis
• Re: [perl #130038] Builtin variable for loop index in foreach by Dave Mitchell
• Re: [perl #130038] Builtin variable for loop index in foreach by Aristotle Pagaltzis
• Re: [perl #130038] Builtin variable for loop index in foreach by Kent Fredric
• Re: [perl #130038] Builtin variable for loop index in foreach by Dave Mitchell
• Re: [perl #130038] Builtin variable for loop index in foreach by Dave Mitchell
• Re: [perl #130038] Builtin variable for loop index in foreach by Kent Fredric
• Re: [perl #130038] Builtin variable for loop index in foreach by Kent Fredric
• [perl #130038] Builtin variable for loop index in foreach by Hugo van der Sanden via RT
• Re: [perl #130038] Builtin variable for loop index in foreach by Zefram
• Re: [perl #130038] Builtin variable for loop index in foreach by Dave Mitchell
• [perl #130038] Builtin variable for loop index in foreach by Ed Avis via RT
• RE: [perl #130038] Builtin variable for loop index in foreach by Ed Avis
• Re: [perl #130038] Builtin variable for loop index in foreach by demerphq
• Re: [perl #130038] Builtin variable for loop index in foreach by Dave Mitchell
• RE: [perl #130038] Builtin variable for loop index in foreach by Ed Avis