Time we switched to unicode? (was Explanation of this Python language feature?)

Rustom Mody rustompmody at gmail.com
Wed Mar 26 05:56:55 CET 2014


On Wednesday, March 26, 2014 10:00:21 AM UTC+5:30, Terry Reedy wrote:
> On 3/25/2014 8:12 PM, Steven D'Aprano wrote:
> > On Tue, 25 Mar 2014 19:55:39 -0400, Terry Reedy wrote:
> >> On 3/25/2014 11:18 AM, Steven D'Aprano wrote:
> >>> The thing is, we can't just create a ∑ function, because it doesn't
> >>> work the way the summation operator works. The problem is that we would
> >>> want syntactic support, so we could write something like this:
> >>>       p = 2
> >>>       ∑(n, 1, 10, n**p)
> >> Of course we can. If we do not insist on separating the dummy name from
> >> the expression that contains it. this works.
> >> def sigma(low, high, func):
> >>       sum = 0
> >>       for i in range(low, high+1):
> >>           sum += func(i)
> >>       return sum
> > There is no expression there. There is a function.
> > You cannot pass an expression to a function in Python,

> One passes an unquoted expression in code by quoting it with either 
> lambda, paired quote marks (Lisp used a single '), or using it in a form 
> that implicitly quotes it (that includes def statements). Unquoted 
> expressions in statements ultimately get passed to an internal functions.

I wrote about the two styles of quoting here:
(Yeah its under the scheme banner)
http://blog.languager.org/2013/08/applying-si-on-sicp.html

There was also a neat little tech report by David Gries from Cornell
explaining that λ ∀ Σ ∫ are all 'binding-constructs' in their own sphere's
[No access to that any more though :-( ]



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