# Example of how to rb\_class\_new\_instance(... rb\_cBignum)?

**URL:** <https://www.ruby-forum.com/t/example-of-how-to-rb-class-new-instance-rb-cbignum/76082>\
**Category:** Ruby\
**Created:** [March 3, 2006, 2:00am UTC](https://www.ruby-forum.com/t/example-of-how-to-rb-class-new-instance-rb-cbignum/76082 "2006-03-03T02:00:37Z")\
**Posts on this page:** 6\
**Page:** 1

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**Author:** ![Clifford\_H](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/49beb7/32.png) [@Clifford\_H](https://www.ruby-forum.com/u/Clifford_H)\
**Post date:** [March 3, 2006, 2:00am UTC](https://www.ruby-forum.com/t/example-of-how-to-rb-class-new-instance-rb-cbignum/76082/1 "2006-03-03T02:00:37Z")

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I’m building a C extension and have a “long long”  
which I want to turn into a Bignum. Can anyone  
point me to an example please? I’ve googled without  
success.

Clifford H…

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**Author:** ![Clifford\_H](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/49beb7/32.png) [@Clifford\_H](https://www.ruby-forum.com/u/Clifford_H)\
**Post date:** [March 3, 2006, 2:09am UTC](https://www.ruby-forum.com/t/example-of-how-to-rb-class-new-instance-rb-cbignum/76082/2 "2006-03-03T02:09:42Z")

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On Mar 2, 2006, at 7:58 PM, Clifford H. wrote:

> I’m building a C extension and have a “long long”  
> which I want to turn into a Bignum. Can anyone  
> point me to an example please? I’ve googled without  
> success.
> 
> Clifford H…

Basing this purely on a random guess (based on reasonable assumptions  
about ruby) try:  
LONGLONG2NUM()

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**Author:** ![Clifford\_H](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/49beb7/32.png) [@Clifford\_H](https://www.ruby-forum.com/u/Clifford_H)\
**Post date:** [March 3, 2006, 2:18am UTC](https://www.ruby-forum.com/t/example-of-how-to-rb-class-new-instance-rb-cbignum/76082/3 "2006-03-03T02:18:47Z")

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On Mar 3, 2006, at 1:58 AM, Clifford H. wrote:

> I’m building a C extension and have a “long long”  
> which I want to turn into a Bignum. Can anyone  
> point me to an example please? I’ve googled without  
> success.
> 
> Clifford H…

VALUE foo = LL2NUM(my\_long);

– Daniel

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<div class="post-metadata">

**Author:** ![Clifford\_H](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/49beb7/32.png) [@Clifford\_H](https://www.ruby-forum.com/u/Clifford_H)\
**Post date:** [March 3, 2006, 2:18am UTC](https://www.ruby-forum.com/t/example-of-how-to-rb-class-new-instance-rb-cbignum/76082/4 "2006-03-03T02:18:47Z")

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Logan C. wrote:

> Basing this purely on a random guess (based on reasonable assumptions  
> about ruby) try:  
> LONGLONG2NUM()

Reasonable guess I suppose, except that doesn’t seem to  
be declared anywhere (ruby 1.8.1-11) :-(.

Clifford.

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**Author:** ![Clifford\_H](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/49beb7/32.png) [@Clifford\_H](https://www.ruby-forum.com/u/Clifford_H)\
**Post date:** [March 3, 2006, 2:39am UTC](https://www.ruby-forum.com/t/example-of-how-to-rb-class-new-instance-rb-cbignum/76082/5 "2006-03-03T02:39:52Z")

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On Mar 2, 2006, at 8:18 PM, Clifford H. wrote:

> Logan C. wrote:
> 
> > Basing this purely on a random guess (based on reasonable  
> > assumptions about ruby) try:  
> > LONGLONG2NUM()
> 
> Reasonable guess I suppose, except that doesn’t seem to  
> be declared anywhere (ruby 1.8.1-11) :-(.
> 
> Clifford.

Hopefully by now you’ve seen Daniel’s more accurate response. (LL2NUM  
(x))

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<div class="post-metadata">

**Author:** ![Clifford\_H](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/49beb7/32.png) [@Clifford\_H](https://www.ruby-forum.com/u/Clifford_H)\
**Post date:** [March 3, 2006, 5:34am UTC](https://www.ruby-forum.com/t/example-of-how-to-rb-class-new-instance-rb-cbignum/76082/6 "2006-03-03T05:34:44Z")

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Daniel H. wrote:

> VALUE foo = LL2NUM(my\_long);

Thanks both. I have my extension working.

Kudos to Matz also - it’s really easy to build these things :-).

Clifford H…