Re: What is the postfix for min long value?
On Tuesday, 6 October 2015 at 15:16:13 UTC, tcak wrote: While writing max ulong value, I added the "u" postfix. So compiler accepted it as ulong value (That's my interpretation if correct on compiler's side). writeln( 18_446_744_073_709_551_615u ); But when I try to print out minimum value of long, compiler says Error: signed integer overflow writeln( -9_223_372_036_854_775_808 ); In case that is the wrong value, I checked it with writeln( long.min ); already. Do I need to put a postfix for that number? I checked documentation by searching "dlang integer" etc, but couldn't have found any information/anything about postfix at all. See above ^^ :D
Re: What is the postfix for min long value?
Jonathan, I saw this answered in another post: http://forum.dlang.org/post/gtaublmskqrhnbhoe...@forum.dlang.org I.e., you can do long(-9223372036854775808UL) :) Or long l = -9223372036854775808UL;
Re: What is the postfix for min long value?
On Tuesday 06 October 2015 17:39, Ali Çehreli wrote: > I would expect the following to work: > > writeln( -9_223_372_036_854_775_808L); > > But it doesn't compile: > >Error: signed integer overflow > > It looks like a compiler bug to me. If so, a very embarrassing one. :) https://issues.dlang.org/show_bug.cgi?id=8929
What is the postfix for min long value?
While writing max ulong value, I added the "u" postfix. So compiler accepted it as ulong value (That's my interpretation if correct on compiler's side). writeln( 18_446_744_073_709_551_615u ); But when I try to print out minimum value of long, compiler says Error: signed integer overflow writeln( -9_223_372_036_854_775_808 ); In case that is the wrong value, I checked it with writeln( long.min ); already. Do I need to put a postfix for that number? I checked documentation by searching "dlang integer" etc, but couldn't have found any information/anything about postfix at all.
Re: What is the postfix for min long value?
On Tuesday, October 06, 2015 15:16:12 tcak via Digitalmars-d-learn wrote: > While writing max ulong value, I added the "u" postfix. So > compiler accepted it as ulong value (That's my interpretation if > correct on compiler's side). > > writeln( 18_446_744_073_709_551_615u ); > > But when I try to print out minimum value of long, compiler says > Error: signed integer overflow > > writeln( -9_223_372_036_854_775_808 ); > > In case that is the wrong value, I checked it with writeln( > long.min ); already. > > Do I need to put a postfix for that number? I checked > documentation by searching "dlang integer" etc, but couldn't have > found any information/anything about postfix at all. L is the prefix to use, but it looks like there's a compiler bug here, because long l = -9_223_372_036_854_775_807L; compiles and long l = -9_223_372_036_854_775_808L; doesn't, even though that's the same as long.min. long l = -9_223_372_036_854_775_807UL; compiles and does the right thing, though that's a pretty silly thing to have to do. Actually, digging through bugzilla, it looks like it's already been reported: https://issues.dlang.org/show_bug.cgi?id=8929 Though since C has the same problem, it's treated as an enhancement rather than a bug (which seems wrong to me). Apparently, the problem stems from the compiler processing the literal and _then_ applying the sign, and long.max is 9_223_372_036_854_775_807L. Apparently, -2L^^63 will work though. All in all, it's probably not a big deal, since you should probably just being using long.min anyway, but this doesn't seem like particularly good behavior to me. - Jonathan M Davis
Re: What is the postfix for min long value?
On 10/06/2015 08:16 AM, tcak wrote: > While writing max ulong value, I added the "u" postfix. Better to use U to be consistent with L (see below). > But when I try to print out minimum value of long, compiler says > Error: signed integer overflow > > writeln( -9_223_372_036_854_775_808 ); I would expect the following to work: writeln( -9_223_372_036_854_775_808L); But it doesn't compile: Error: signed integer overflow It looks like a compiler bug to me. If so, a very embarrassing one. :) (You can use UL and LU as well.) > Do I need to put a postfix for that number? I checked documentation by > searching "dlang integer" etc, but couldn't have found any > information/anything about postfix at all. They go by "suffix". The officital documentation: http://dlang.org/lex.html#integerliteral My short mention of them start at the section "The L suffix": http://ddili.org/ders/d.en/literals.html#ix_literals.literal (They were missing in my index section. Adding now...) Ali
