string interpolation syntactic sugar

[Fredrik Lundh]

Dickon Reed <dr10009 at cl.cam.ac.uk> wrote:
> I propose a new kind of string literal wherein bracketed expressions
> are evaluated then converted to strings.

argh!

> An alternative approach might have a function to do this:
> 
> interpolate("a {x} b {y}")

that's reasonable.

> I wonder if this could be implemented as a library service (if it
> hasn't already been done). Is it as simple as chopping up the string
> and calling str(eval(foo)) on each bracketted component? The place I
> come unstuck with this is obtaining the globals and locals of the
> caller so that the expressions are evaluated in the environment where
> interpolate is called.

I'm not sure if it works with 1.5.2, but Ping's string
interpolation module implements most of this (with
a slightly different syntax).

start here:

    http://www.lfw.org/python/

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