# Array.each

**URL:** <https://rubytalk.org/t/array-each/6752>\
**Category:** ruby-talk\
**Created:** [8 July 2003 19:00 UTC](https://rubytalk.org/t/array-each/6752 "2003-07-08T19:00:36Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Berger\_Daniel2](https://avatars.discourse-cdn.com/v4/letter/b/9fc348/32.png) [@Berger\_Daniel2](https://rubytalk.org/u/Berger_Daniel2)\
**Post date:** [8 July 2003 19:00 UTC](https://rubytalk.org/t/array-each/6752/1 "2003-07-08T19:00:36Z")

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> Gentelmans: …(There are any woman around there ?)
> 
> I would love to be able to do:
> 
> a=(1…10)

With this code, ‘a’ becomes a single Range. Try: a = \*1…10.

> a.each {| x , y| p x }
> 
> 1  
> 3  
> 5  
> 7  
> 9

You’ll have to redefine each() to yield two elements instead of one in order  
to get this behavior. Or you could just use step:

0.step(a.length,2){ |i| p a[i] }

> (IMHO … following the principle of the least surprise…may it  
> should be a native behavior .)

You mean Ruby should automatically yield as many parameters as the block  
expects? You’ll have to talk to Matz about that one. 🙂

Regards,

Dan

---

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**Author:** ![Guillaume\_Marcais1](https://avatars.discourse-cdn.com/v4/letter/g/46a35a/32.png) [@Guillaume\_Marcais1](https://rubytalk.org/u/Guillaume_Marcais1)\
**Post date:** [8 July 2003 20:09 UTC](https://rubytalk.org/t/array-each/6752/2 "2003-07-08T20:09:40Z")

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> > Gentelmans: …(There are any woman around there ?)
> > 
> > I would love to be able to do:
> > 
> > a=(1…10)
> 
> With this code, ‘a’ becomes a single Range. Try: a = \*1…10.
> 
> > a.each {| x , y| p x }
> > 
> > 1  
> > 3  
> > 5  
> > 7  
> > 9
> 
> You’ll have to redefine each() to yield two elements instead of one in order  
> to get this behavior. Or you could just use step:
> 
> 0.step(a.length,2){ |i| p a[i] }
> 
> > (IMHO … following the principle of the least surprise…may it  
> > should be a native behavior .)
> 
> You mean Ruby should automatically yield as many parameters as the block  
> expects? You’ll have to talk to Matz about that one. 🙂

Something like that?

[gus@comp ex]$ cat eachn.rb  
module Enumerable  
def each\_n(&b)  
i =   
n = b.arity  
n = -n if n \<= 1  
k = n  
self.each { |x|  
i \<\< x  
k -= 1  
if k \<= 0  
b.call(\*i)  
i =   
k = n  
end  
}  
unless i.empty?  
i += Array.new(n - i.length)  
b.call(\*i) unless i.empty?  
end  
end  
end

if **FILE** == $0  
(0…10).each\_n { |x| puts “x %s” % x.inspect }  
(0…10).each\_n { |x, y| puts “x %s y %s” % [x.inspect, y.inspect] }  
(0…10).each\_n { |x, y, z| puts “x %s y %s z %s” % [x.inspect,  
y.inspect, z.inspect] }  
.each\_n { |x, y| puts “Huh?” }  
end

[gus@comp ex]$ ruby eachn.rb  
x 0  
x 1  
x 2  
x 3  
x 4  
x 5  
x 6  
x 7  
x 8  
x 9  
x 10  
x 0 y 1  
x 2 y 3  
x 4 y 5  
x 6 y 7  
x 8 y 9  
x 10 y nil  
x 0 y 1 z 2  
x 3 y 4 z 5  
x 6 y 7 z 8  
x 9 y 10 z nil

Guillaume.

> **···**
>
> On Tue, 2003-07-08 at 15:00, Berger, Daniel wrote:
> 
> > Regards,
> > 
> > Dan