fluid-let?

[Marek Kubica]

Hi,

Is there a way to get fluid-let for Guile? Or something like
<http://everything2.com/title/Teach+Yourself+Scheme%253A+5.2+fluid-let>?

I am having a mutable hash object that I don't want to pass as an
argument to every single function that I call, I'd prefer to use a
similar solution to what the ports do, by redefining the default input
port "semi-globally".

I saw this: <http://paste.lisp.org/display/28213> but it does not work
with mutating the fluids.

regards,
Marek