Pass variable by reference

[Rustom Mody]

On Wednesday, May 7, 2014 8:09:34 AM UTC+5:30, Chris Angelico wrote:
> On Wed, May 7, 2014 at 12:18 PM, Rustom Mody wrote:
> > Wrong conclusion!
> > These 3 lines look the same and amount to much the same in python and C.
> > But as the example widens to something beyond 3 lines, the difference
> > will become more and more significant

> Python, C, REXX, BASIC, and pretty much anything else with a broadly
> imperative style.

> The thing is, though, the difference between one language's variable
> semantics and another's is similar to, as Ned said, the difference
> between one language's integer semantics and another's. What happens
> in C when you do this?

> x = 1 << 31;
> x += x;

> The only possible answer is "it depends", as you can't know how big an
> int is, but certainly it's of finite size. In Python, the equivalent
> is guaranteed to put 2**32 into x, because integers store arbitrary
> precision. That's a pretty important difference, yet we're happy to
> call both "integer". A Python list is very different from a LISP list.
> A Python array is very different from a Pike array. A Python function
> is very different from a mathematical function. Why do we object to
> the difference in "variable" but not the others?

> Yes, there are differences. That's why we have different languages;
> you can't do a minimalist transformation of source code and expect
> exactly identical semantics. But we start with familiar names that
> will give people some idea of what's going on.


The number of possible concepts is infinite

The number of words is finite (even assuming unicode!!)

IOW A combinatorial problem...