[perl #68078] List::Util::sum and Math::BigInt don't play nice with each other.

# New Ticket Created by  Abigail 
# Please include the string:  [perl #68078]
# in the subject line of all future correspondence about this issue. 
# <URL: http://rt.perl.org/rt3/Ticket/Display.html?id=68078 >



This is a bug report for perl from abigail@abigail.be,
generated with the help of perlbug 1.36 running under perl 5.10.0.


-----------------------------------------------------------------
[Please enter your report here]

Imagine you want to sum the first 50 factorials. You might want to
write that as:

    use List::Util 'sum';
    use Math::BigInt;

    my @facs = map {Math::BigInt -> new ($_) -> bfac} 1 .. 50;
    say sum @facs;

This unfortunally doesn't give you all the digits; it prints:

    3.10350532295461997e+64

But if you reinvent the wheel, and do the summing by hand:

    my  @facs = map {Math::BigInt -> new ($_) -> bfac} 1 .. 50;
    my  $sum  = 0;
        $sum += $_ for @facs;
    say $sum;

you do get all the digits:

    31035053229546199656252032972759319953190362094566672920420940313


This is quite unfortunate.


[Please do not change anything below this line]
-----------------------------------------------------------------
---
Flags:
    category=library
    severity=low
---
Site configuration information for perl 5.10.0:

Configured by abigail at Sat Dec 22 18:46:30 CET 2007.

Summary of my perl5 (revision 5 version 10 subversion 0) configuration:
  Platform:
    osname=linux, osvers=2.6.11-1.1369_fc4smp, archname=i686-linux-64int-ld
    uname='linux almanda 2.6.11-1.1369_fc4smp #1 smp thu jun 2 23:08:39 edt 2005 i686 i686 i386 gnulinux '
    config_args='-des -Dusemorebits -Uversiononly -Dmydomain=.abigail.be -Dcf_email=abigail@abigail.be -Dperladmin=abigail@abigail.be -Doptimize=-g -Dcc=gcc -Dprefix=/opt/perl -Dusemorebits'
    hint=recommended, useposix=true, d_sigaction=define
    useithreads=undef, usemultiplicity=undef
    useperlio=define, d_sfio=undef, uselargefiles=define, usesocks=undef
    use64bitint=define, use64bitall=undef, uselongdouble=define
    usemymalloc=n, bincompat5005=undef
  Compiler:
    cc='gcc', ccflags ='-DDEBUGGING -fno-strict-aliasing -pipe -I/usr/local/include -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -I/usr/include/gdbm',
    optimize='-g',
    cppflags='-DDEBUGGING -fno-strict-aliasing -pipe -I/usr/local/include -I/usr/include/gdbm'
    ccversion='', gccversion='4.0.2 20051125 (Red Hat 4.0.2-8)', gccosandvers=''
    intsize=4, longsize=4, ptrsize=4, doublesize=8, byteorder=12345678
    d_longlong=define, longlongsize=8, d_longdbl=define, longdblsize=12
    ivtype='long long', ivsize=8, nvtype='long double', nvsize=12, Off_t='off_t', lseeksize=8
    alignbytes=4, prototype=define
  Linker and Libraries:
    ld='gcc', ldflags =' -L/usr/local/lib'
    libpth=/usr/local/lib /lib /usr/lib
    libs=-lnsl -lgdbm -ldb -ldl -lm -lcrypt -lutil -lc
    perllibs=-lnsl -ldl -lm -lcrypt -lutil -lc
    libc=/lib/libc-2.3.5.so, so=so, useshrplib=false, libperl=libperl.a
    gnulibc_version='2.3.5'
  Dynamic Linking:
    dlsrc=dl_dlopen.xs, dlext=so, d_dlsymun=undef, ccdlflags='-Wl,-E'
    cccdlflags='-fPIC', lddlflags='-shared -g -L/usr/local/lib'

Locally applied patches:
    

---
@INC for perl 5.10.0:
    /home/abigail/Perl
    /opt/perl/lib/5.10.0/i686-linux-64int-ld
    /opt/perl/lib/5.10.0
    /opt/perl/lib/site_perl/5.10.0/i686-linux-64int-ld
    /opt/perl/lib/site_perl/5.10.0
    /opt/perl/lib/site_perl/5.8.8
    /opt/perl/lib/site_perl
    .

---
Environment for perl 5.10.0:
    HOME=/home/abigail
    LANG=en_US.UTF-8
    LANGUAGE (unset)
    LC_CTYPE=en_US.utf8
    LC_MESSAGES=en_US.utf8
    LD_LIBRARY_PATH=/home/abigail/Lib:/usr/local/lib:/usr/lib:/lib:/usr/X11R6/lib
    LOGDIR (unset)
    PATH=/home/abigail/Bin:/opt/perl/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/sbin:/usr/sbin:/sbin:/usr/X11R6/bin:/usr/games:/opt/git/bin:/home/abigail/Perl/Photos:/home/abigail/Perl/Bin:/opt/mysql/bin
    PERL5LIB=/home/abigail/Perl
    PERLDIR=/opt/perl
    PERL_BADLANG (unset)
    SHELL=/bin/bash

• [perl #68078] List::Util::sum and Math::BigInt don't play nice with each other. by Abigail
• Re: [perl #68078] List::Util::sum and Math::BigInt don't play nicewith each other. by Graham Barr
• Re: [perl #68078] List::Util::sum and Math::BigInt don't play nicewith each other. by Abigail