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Re: "Python for Lisp Programmers"



McCarthy used parens for grouping in the original Lisp paper

http://www-formal.stanford.edu/jmc/recursive/node3.html

probably because parens are usually used for grouping in math,
which is what Lisp was at that point.

I considered using some alternatives to parens for s-expressions
in Arc, but decided to stick with parens.  They are more
directional than square brackets, which is important when
you have nested delimiters. Screen versions of l and r parens 
overlap in about 3 pixels, whereas square brackets overlap in all 
but 2 pixels. Compare )( and ][.  Angle-brackets are the most
directional (and would have given added hipness points for
looking like html/xml ;-) but don't seem to enclose expressions
as much.


> Historical question: Ergonomically, Parentheses are annoying because
> they
> require constant use of the SHIFT key.  Square brackets would have
> been a
> better choice.  Who chose parentheses and why?
> 
> Note: the argument that, if square brackets were better, people would
> use
> them loses to the argument that network externalities make everyone
> do the
> same thing even if it is suboptimal (worse-is-better, microsoft,
> etc).
> The holds for infix Lisp and infix scheme.
> 
> -Alex-
> 
> ___________________________________________________________________
> S. Alexander Jacobson                   i2x Media
> 1-917-783-0889 voice                    1-212-697-1427 fax
> 
> 


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