[Python-Dev] A Hygienic Macro System in Python?

[Duncan Booth]

On 20 Mar 2002, barry@zope.com (Barry A. Warsaw) wrote:

> In the following example, imagine that
> 
>     using <expr>:
>      suite()
> 
> is syntactic sugar for:
> 
>     using(<expr>, suite)
> 
> 

How about imagining:
    	using <expr>:
    	   suite

is syntactic sugar for:
     anon1 = <expr>
     for anon2 in anon1:
         try:
              suite
         except:
              anon1.throw() # Assuming PEP279 part 3

def WithLock():
    print "Acquiring lock"
    try:
        yield None
    finally:
        print "Releasing lock"

using WithLock():
    doSomethingCritical()

-- 
Duncan Booth                                             duncan@rcp.co.uk
int month(char *p){return(124864/((p[0]+p[1]-p[2]&0x1f)+1)%12)["\5\x8\3"
"\6\7\xb\1\x9\xa\2\0\4"];} // Who said my code was obscure?