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digitalmars.D - Negative index for arrays

reply Muta <komuta gmail.com> writes:
I see that this is used in Python's strings, to get a char from the end of
the string. Would there be any drawback in implementing the same thing in
D's arrays ? Something like :
array[-x] = array[array.length - x]
Mar 22 2006
parent reply Oskar Linde <oskar.lindeREM OVEgmail.com> writes:
Muta skrev:
 I see that this is used in Python's strings, to get a char from the end of
 the string. Would there be any drawback in implementing the same thing in
 D's arrays ? Something like :
 array[-x] = array[array.length - x]

The drawback I can see is that it needs a runtime check every time an array is indexed. I would classify that as a stopper. Instead, in D, you can write: array[$-1] /Oskar
Mar 22 2006
parent Jacques <Jacques_member pathlink.com> writes:
In article <dvrapu$cpd$1 digitaldaemon.com>, Oskar Linde says...
Muta skrev:
 I see that this is used in Python's strings, to get a char from the end of
 the string. Would there be any drawback in implementing the same thing in
 D's arrays ? Something like :
 array[-x] = array[array.length - x]

The drawback I can see is that it needs a runtime check every time an array is indexed. I would classify that as a stopper. Instead, in D, you can write: array[$-1] /Oskar

You can always fake it. In the following code i can be either positive or negative: array[(i+$)%$] Jacques
Mar 22 2006