[Python-ideas] Quick idea: defining variables from functions that take the variable name

[Steven D'Aprano]

On Tue, May 31, 2016 at 11:13:30AM -0700, Brendan Barnwell wrote:

> ># okay
> >name -> sympy.Symbol()
> 
> 	I don't like this that much, because it looks odd to have the 
> expression on the right without the argument.  The syntax doesn't make 
> it at all clear how the T gets used on the RHS.

*shrug*

You have to learn it, just like you have to learn decorator syntax. It's 
literally a *one sentence explanation*:

"The name on the left hand side is passed to the function on the right 
hand side, as a string, as the first positional argument."


[...]
> > But this is allowed:
> >
> > my_name -> f(g())  # like f('my_name', g())
> 
> 	So. . . what exactly will be allowed?

Guido suggested that we restrict it similar to the restrictions on 
decorator syntax. I'd be okay with that. Without looking up the syntax, 
from memory:

@decorate
@name.decorate
@factory()  # no arguments, returns a decorator
@factory(args, keyword=foo)

and possibly a few others. So by analogy:

x -> Function()
x -> module.Function()
x -> module.Function(args, keyword=foo)

etc.


-- 
Steve