variables with loop-local scope?

[Alex Martelli]

Brian Alexander wrote:

> I remember using a language many years ago that permitted the creation
> of temporary, local variables within the body of a loop (and perhaps
> other statement blocks.) Maybe it was Turing.

Or C (not that exotic, but does have block-local variables, as do its
descendants).

> Can Python do this?

Python's variables _automatically_ go out of scope only when a function
terminates (you can of course explicitly delete them).  So, if you need
"automatic going out of scope", you need a nested function.  E.g.:

> for i in listOfNames:
>    prefixMr = 'Mr'
>    prefixMs = 'Ms'
> 
>    if i in mansName:
>      salutation = prefixMr + i
> 
>    else:
>      salutation = prefixMs + i
> 
>    print 'Hello,' + salutation

for i in listOfNames:
   def block():
     prefixMr = 'Mr'
     prefixMs = 'Ms'
 
     if i in mansName:
       salutation = prefixMr + i
     else:
       salutation = prefixMs + i
     print 'Hello,' + salutation
   block()


Alex