# BigDecimal#to\_i/to\_int $B$N5sF0$K$D$$$F(B

**URL:** <https://www.ruby-forum.com/t/bigdecimal-to-i-to-int-b-n5sf0-k-d-f-b/177200>\
**Category:** Development\
**Created:** [October 13, 2009, 9:44am UTC](https://www.ruby-forum.com/t/bigdecimal-to-i-to-int-b-n5sf0-k-d-f-b/177200 "2009-10-13T09:44:01Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![KAKUTANI\_Shintaro](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/9fc348/32.png) [@KAKUTANI\_Shintaro](https://www.ruby-forum.com/u/KAKUTANI_Shintaro)\
**Post date:** [October 13, 2009, 9:44am UTC](https://www.ruby-forum.com/t/bigdecimal-to-i-to-int-b-n5sf0-k-d-f-b/177200/1 "2009-10-13T09:44:01Z")

</div>

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rubyspec  
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BigDecimale$B$Ge(B Infinitye$B$He(BNaN e$B$re(B to\_i/to\_int  
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(e$BF0$+$7$F$$$k%P!\<%8%g%s$,\>/$7A0$N$b$N$G62=L$G$9e(B)

$ /usr/bin/ruby -v -rbigdecimal -e ‘%w[Infinity NaN].each{|s| v =  
BigDecimal.new(s); i = v.to\_i rescue $!.class; print “#{v}:”;p i}’  
ruby 1.8.6 (2008-08-11 patchlevel 287) [universal-darwin9.0]  
Infinity:nil  
NaN:nil

$ ruby -v -rbigdecimal -e ‘%w[Infinity NaN].each{|s| v =  
BigDecimal.new(s); i = v.to\_i rescue $!.class; print “#{v}:”;p i}’  
ruby 1.8.7 (2009-06-12 patchlevel 174) [i686-darwin9]  
Infinity:FloatDomainError  
NaN:FloatDomainError

$ ruby19 -v -rbigdecimal -e ‘%w[Infinity NaN].each{|s| v =  
BigDecimal.new(s); i = v.to\_i rescue $!.class; print “#{v}:”;p i}’  
ruby 1.9.2dev (2009-10-05 trunk 25235) [i386-darwin9.8.0]  
Infinity:FloatDomainError  
NaN:FloatDomainError

e$B$k$j$^$N5-=R$Oe(B1.8e$B$be(B1.9e$B$b!Ve(BInfinity e$B$de(B NaN  
e$B$N$H$-!"e(Bi e$B$Oe(B nil e$B$K$J$j$^$9!W$G$7$?!#e(B  
[http://doc.okkez.net/187/view/method/BigDecimal/i/to\_i](http://doc.okkez.net/187/view/method/BigDecimal/i/to_i)  
[http://doc.okkez.net/192/view/method/BigDecimal/i/to\_i](http://doc.okkez.net/192/view/method/BigDecimal/i/to_i)

e$B\<j85$G\<:GT$7$?e(Bspece$B$O!"e(B  
[http://github.com/rubyspec/rubyspec/blob/master/library/bigdecimal/shared/to\_int.rb](http://github.com/rubyspec/rubyspec/blob/master/library/bigdecimal/shared/to_int.rb)  
e$B$Ne(B5e$B9TL$He(B6e$B9TL$G$9!#e(B

---

<div class="post-metadata">

**Author:** ![KAKUTANI\_Shintaro](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/9fc348/32.png) [@KAKUTANI\_Shintaro](https://www.ruby-forum.com/u/KAKUTANI_Shintaro)\
**Post date:** [October 14, 2009, 4:38am UTC](https://www.ruby-forum.com/t/bigdecimal-to-i-to-int-b-n5sf0-k-d-f-b/177200/2 "2009-10-14T04:38:00Z")

</div>

e$B:XF#$H?=$7$^$9!#e(B

On Tue, 13 Oct 2009 16:43:24 +0900  
KAKUTANI Shintaro [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:

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> ruby 1.8.7 (2009-06-12 patchlevel 174) [i686-darwin9]  
> Infinity:FloatDomainError  
> NaN:FloatDomainError

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r23645 | shyouhei | 2009-06-08 08:37:55 +0900 (Mon, 08 Jun 2009) | 10  
lines

merge revision(s) 23610:23613:  
\* ext/bigdecimal/bigdecimal.c (VpAlloc): avoid ALLOCA\_N() to  
avoid  
segmentation fault caused by (insanely) long decimal values.  
backported from 1.9.  
\* ext/bigdecimal/bigdecimal.c (BigDecimal\_dump, BigDecimal\_to\_i,  
BigDecimal\_to\_f, BigDecimal\_to\_s, BigDecimal\_split,  
BigDecimal\_inspect): ditto.  
\* ext/bigdecimal/bigdecimal.c (BigDecimal\_to\_f): returns Inf if  
exp is bigger than DBL\_MANT\_DIG.

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r23613 | matz | 2009-06-01 09:14:25 +0900 (e$B7ne(B, 01 6e$B7ne(B 2009)  
| 6 lines

- ext/bigdecimal/bigdecimal.c (VpAlloc): avoid ALLOCA\_N() to avoid  
segmentation fault caused by (insanely) long decimal values.  
backported from 1.9.
- ext/bigdecimal/bigdecimal.c (BigDecimal\_dump, BigDecimal\_to\_i,  
BigDecimal\_to\_f, BigDecimal\_to\_s, BigDecimal\_split,  
BigDecimal\_inspect): ditto.

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> $ ruby19 -v -rbigdecimal -e ‘%w[Infinity NaN].each{|s| v = BigDecimal.new(s); i = v.to\_i rescue $!.class; print “#{v}:”;p i}’  
> ruby 1.9.2dev (2009-10-05 trunk 25235) [i386-darwin9.8.0]  
> Infinity:FloatDomainError  
> NaN:FloatDomainError

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---

<div class="post-metadata">

**Author:** ![KAKUTANI\_Shintaro](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/k/9fc348/32.png) [@KAKUTANI\_Shintaro](https://www.ruby-forum.com/u/KAKUTANI_Shintaro)\
**Post date:** [October 15, 2009, 4:28am UTC](https://www.ruby-forum.com/t/bigdecimal-to-i-to-int-b-n5sf0-k-d-f-b/177200/3 "2009-10-15T04:28:51Z")

</div>

Tadashi S. e$B$5$s$O=q$-$^$7$?e(B:

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