[Issue 6023] std.random.uniform and std.bigint.BigInt compilation error
https://issues.dlang.org/show_bug.cgi?id=6023 berni44 changed: What|Removed |Added Status|NEW |RESOLVED CC||bugzi...@d-ecke.de Resolution|--- |WONTFIX --
[Issue 6023] std.random.uniform and std.bigint.BigInt compilation error
https://issues.dlang.org/show_bug.cgi?id=6023 Andrei Alexandrescu changed: What|Removed |Added Keywords||bootcamp CC||and...@erdani.com --
[Issue 6023] std.random.uniform and std.bigint.BigInt compilation error
http://d.puremagic.com/issues/show_bug.cgi?id=6023 Joseph Rushton Wakeling changed: What|Removed |Added CC||joseph.wakel...@webdrake.ne ||t --- Comment #7 from Joseph Rushton Wakeling 2013-08-30 04:41:06 PDT --- (In reply to comment #0) > uniform function from standard library doesn't work correctly with standard > BigInt. There are no indications anywhere that it shouldn't work, so I think > it is a bug. Typical existing RNGs may be expected to have an underlying range of 0 .. uint.max, with others perhaps extending that to ulong.max. They inherently can't cover the range of possible values that a BigInt can be expected to take, so there's a strong potential for statistical problems (albeit that those maxima are Very Big Indeed). It might be possible to do some customization so that BigInts falling within the appropriate bounds can be used -- probably your best bet would be to convert to uints, call the integral-type uniform() and convert back -- but in general generating random BigInts would require a BigInt-dedicated RNG. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email --- You are receiving this mail because: ---
[Issue 6023] std.random.uniform and std.bigint.BigInt compilation error
http://d.puremagic.com/issues/show_bug.cgi?id=6023 --- Comment #6 from Don 2012-06-21 02:54:00 PDT --- (In reply to comment #5) > (In reply to comment #4) > > > Because BigInt type is not integral. > > > > import std.traits; > > pragma(msg, isIntegral!BigInt); // pritns false > > Maybe we'll need to add to std.traits a new trait that's true for all integral > values, BigInts too. It's a bit difficult. If BigInt used the same algorithm for random number generation that built-in ints use, the performance would be horrible. For an n-byte number, you'd have O(2n) memory allocations on average, with an unbounded worst case, instead of the single allocation you'd have with a dedicated algorithm. And generating a string of 1 million random bits is the sort of thing that somebody is likely to do. Supporting it with terrible performance isn't any better than not supporting it at all. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email --- You are receiving this mail because: ---
[Issue 6023] std.random.uniform and std.bigint.BigInt compilation error
http://d.puremagic.com/issues/show_bug.cgi?id=6023
--- Comment #4 from Kenji Hara 2012-05-19 18:38:45 PDT ---
Original sample code cannot yet compile, but error messages are different.
C:\dmd2\src\phobos\std\random.d(1045): Error: template std.random.uniform does
not match any function template declaration
C:\dmd2\src\phobos\std\random.d(1043): Error: template std.random.uniform
cannot deduce template function from argument types
!("[]",igInt,BigInt,MersenneTwisterEngine!(uint,32,624,397,31,-1727483681u,11,7,-1658038656u,15,-272236544u,18))(BigInt,BigInt,MersenneTwistrEngine!(uint,32,624,397,31,-1727483681u,11,7,-1658038656u,15,-272236544u,18))
C:\dmd2\src\phobos\std\random.d(1045): Error: template instance
uniform!("[]",BigInt,BigInt,MersenneTwisterEngine!(uint,32,624,397,31-1727483681u,11,7,-1658038656u,15,-272236544u,18))
errors instantiating template
test.d(8): Error: template instance std.random.uniform!("[]",BigInt,BigInt)
error instantiating
test.d(8): Error: template std.bigint.BigInt.__ctor does not match any function
template declaration
C:\dmd2\src\phobos\std\bigint.d(82): Error: template std.bigint.BigInt.__ctor
cannot deduce template function from argument types !()_error_)
Because BigInt type is not integral.
import std.traits;
pragma(msg, isIntegral!BigInt); // pritns false
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[Issue 6023] std.random.uniform and std.bigint.BigInt compilation error
http://d.puremagic.com/issues/show_bug.cgi?id=6023 Don changed: What|Removed |Added CC||clugd...@yahoo.com.au --- Comment #3 from Don 2011-06-11 00:49:41 PDT --- (In reply to comment #1) > The error message is the one returned when std.conv.to!string(BigInt) is > called. > > std.bigint doesn't support std.conv.to!string. (You know all about this from > 5231.) This has been reported several times already. More accurately, to!string doesn't support std.bigint. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email --- You are receiving this mail because: ---
[Issue 6023] std.random.uniform and std.bigint.BigInt compilation error
http://d.puremagic.com/issues/show_bug.cgi?id=6023 --- Comment #2 from Vladimir Matveev 2011-06-10 23:48:18 PDT --- (In reply to comment #1) > The error message is the one returned when std.conv.to!string(BigInt) is > called. > > std.bigint doesn't support std.conv.to!string. (You know all about this from > 5231.) This has been reported several times already. Yes, I know. But isn't it strange that the standard library is inconsistent with itself? Shouldn't decisions like "remove a function which other parts of library expect to be" be more deliberate? I haven't seen such problems in any of the languages I used, and I think it is not good for the language itself to have them. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email --- You are receiving this mail because: ---
[Issue 6023] std.random.uniform and std.bigint.BigInt compilation error
http://d.puremagic.com/issues/show_bug.cgi?id=6023 Paul D. Anderson changed: What|Removed |Added CC||paul.d.ander...@comcast.net --- Comment #1 from Paul D. Anderson 2011-06-10 13:21:45 PDT --- The error message is the one returned when std.conv.to!string(BigInt) is called. std.bigint doesn't support std.conv.to!string. (You know all about this from 5231.) This has been reported several times already. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email --- You are receiving this mail because: ---
