<br><br><div class="gmail_quote">On Mon, Oct 18, 2010 at 4:41 PM, Bert Freudenberg <span dir="ltr"><<a href="mailto:bert@freudenbergs.de">bert@freudenbergs.de</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div><div></div><div class="h5">On 18.10.2010, at 13:49, Colin Putney wrote:<br>
<br>
> On Mon, Oct 18, 2010 at 1:38 PM, Eliot Miranda <<a href="mailto:eliot.miranda@gmail.com">eliot.miranda@gmail.com</a>> wrote:<br>
><br>
>> I think immediate characters are much more generally useful, especially<br>
>> considering unicode. The current implementation of only codes 0 to 255<br>
>> being == is error-prone.<br>
><br>
> I enthusiastically agree. I think string handling in Squeak is pretty<br>
> weak, and having efficient Characters would provide a solid basis for<br>
> improving it.<br>
<br>
</div></div>Disagree.<br>
<br>
You don't want to be manipulating single characters if speed matters. Much better to add primitive support to speed up WideStrings.<br></blockquote><div><br></div><div>But there are many places in the system that deal with characters. They are an extremely common datatype in the compiler, in the UI.</div>
<div><br></div><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Also, adding more immediate objects will slow down the system as a whole. I remember changing the tag bit check in the early days of Squeak did have a performance impact. Whether new immediates would result in a net speed win remains to be seen.<br>
</blockquote><div><br></div><div>It won't slow the system down, and I speak form VW experience where we had either immediate characters and integers (32-bit) or immediate characters integers and floats (64-bits). You're basically talking about the cost of masking by 1 or masking by 3 (or 7 in 64-bits) and on last century's machines that could make a difference. But on contemporary hardware it makes no difference; only memory access makes a difference and adding immediate characters can only reduce memory access. Therefore it will likely speed-up the system, but will certainly not slow it down.</div>
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- Bert -<br>
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