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Date: Wed, 06 May 2015 16:23:08 -0400
From: Dave Angel <davea@davea.name>
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Subject: Re: Throw the cat among the pigeons
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On 05/06/2015 11:36 AM, Alain Ketterlin wrote:
> Yes, plus the time for memory allocation. Since the code uses "r *=
> ...", space is reallocated when the result doesn't fit. The new size is
> probably proportional to the current (insufficient) size. This means
> that overall, you'll need fewer reallocations, because allocations are
> made in bigger chunks.

That sounds plausible, but  a=5; a*=4  does not update in place. It 
calculates and creates a new object.  Updating lists can work as you 
say, but an int is immutable.

It's an optimization that might be applied if the code generator were a 
lot smarter, (and if the ref count is exactly 1), but it would then be 
confusing to anyone who used id().

-- 
DaveA