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digitalmars.D.learn - std.range.zip and tuple labels

reply Joseph Rushton Wakeling <joseph.wakeling webdrake.net> writes:
Hi all,

If I use zip() to collate together one or more ranges, the individual elements
get returned as a Tuple of the corresponding types.

Is there any way to get zip to label those elements, i.e. to return e.g.

	Tuple!(int, "one", float, "two")

instead of

	Tuple!(int, float)

.... ?
May 15 2013
parent reply "bearophile" <bearophileHUGS lycos.com> writes:
Joseph Rushton Wakeling:

 If I use zip() to collate together one or more ranges, the 
 individual elements
 get returned as a Tuple of the corresponding types.

 Is there any way to get zip to label those elements, i.e. to 
 return e.g.
See: http://d.puremagic.com/issues/show_bug.cgi?id=8715 I think currently you have to use map!() to replace the tuple. Maybe am unsafe map-cast suffices: import std.stdio, std.range, std.algorithm, std.typecons; void main() { auto r1 = zip(["red", "blue"], [10, 20]); r1.writeln; alias T2 = Tuple!(string,"col", int,"val"); r1.map!(r => T2(r[])).writeln; r1.map!(r => cast(T2)r).writeln; } Bye, bearophile
May 15 2013
parent Joseph Rushton Wakeling <joseph.wakeling webdrake.net> writes:
On 05/15/2013 08:00 PM, bearophile wrote:
 I think currently you have to use map!() to replace the tuple. Maybe am unsafe
 map-cast suffices:
Feels a bit nasty, and I have the feeling it would probably slow things down ... ? :-( I like the zipWith idea, though I can't help but wish zip() itself was flexible enough to allow something like, zip(arr1, "one", arr2, "two") ... though I guess that would fall over if you ever wanted to use zip to lock together two immutable strings.
May 15 2013