# Enumerable can't take multiple parameters

**URL:** <https://www.ruby-forum.com/t/enumerable-cant-take-multiple-parameters/124086>\
**Category:** Development\
**Created:** [December 24, 2007, 2:26pm UTC](https://www.ruby-forum.com/t/enumerable-cant-take-multiple-parameters/124086 "2007-12-24T14:26:36Z")\
**Posts on this page:** 5\
**Page:** 1

<div class="post-metadata">

**Author:** ![GOTOU\_Yuuzou](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/a88e4f/32.png) [@GOTOU\_Yuuzou](https://www.ruby-forum.com/u/GOTOU_Yuuzou)\
**Post date:** [December 24, 2007, 2:26pm UTC](https://www.ruby-forum.com/t/enumerable-cant-take-multiple-parameters/124086/1 "2007-12-24T14:26:36Z")

</div>

eache$B$GJ#?t$N%Q%i%a!\<%?$re(Byielde$B$7$?$H$-$K!"e(BEnumerable#colecte$B$G!"e(B  
e$B@hF,$NCM$7$+\<u$1\<h$l$J$$$h$&$G$9!#e(B

% ruby-1.9 -v -e ’  
~  
class Foo  
include Enumerable  
def each  
{1=\>2, 3=\>4}.each{|k, v|  
yield(k, v)  
}  
end  
end

foo=Foo.new  
foo.each{|k, v| p [k, v] }  
foo.collect{|k, v| p [k, v] }  
’  
ruby 1.9.0 (2007-12-24 revision 0) [x86\_64-linux]  
[1, 2]  
[3, 4]  
[1, nil]  
[3, nil]

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e$BB&$NLdBj$J$N$+H=CG$G$-$^$;$s$G$7$?!#e(B

— lib/rexml/element.rb (revision 14606)  
+++ lib/rexml/element.rb (working copy)  
@@ -1013,7 +1013,7 @@  
# doc.root.attributes.each {|name, value| p name+" =\> "+value }  
def each  
each\_attribute do |attr|

- 

```
   yield attr.expanded_name, attr.value

```

- 

```
   yield [attr.expanded_name, attr.value]
 end

```

end

---

<div class="post-metadata">

**Author:** ![GOTOU\_Yuuzou](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/a88e4f/32.png) [@GOTOU\_Yuuzou](https://www.ruby-forum.com/u/GOTOU_Yuuzou)\
**Post date:** [December 24, 2007, 5:02pm UTC](https://www.ruby-forum.com/t/enumerable-cant-take-multiple-parameters/124086/2 "2007-12-24T17:02:04Z")

</div>

e$B$^$D$b$He(B e$B$f$-$R$m$G$9e(B

In message “Re: [ruby-dev:32708] Enumerable can’t take multiple  
parameters”  
on Mon, 24 Dec 2007 22:25:54 +0900, GOTOU Yuuzou  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) writes:

|eache$B$GJ#?t$N%Q%i%a!\<%?$re(Byielde$B$7$?$H$-$K!"e(BEnumerable#colecte$B$G!"e(B  
|e$B@hF,$NCM$7$+\<u$1\<h$l$J$$$h$&$G$9!#e(B

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e$B$H$$$&LdBj$G$9!#8=:\_$Oe(B

module Enumerable  
def collect  
result = []  
self.each{|x| result.push(yield x)}  
result  
end  
end

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module Enumerable  
def collect  
result = []  
self.each{|\*x| result.push(yield \*x)}  
result  
end  
end

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|e$B$3$N1F6A$G!"e(BRSSe$B$N%F%9%H$,\<:GT$7$F$$$^$9!#e(B  
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```
                            e$B$^$D$b$He(B e$B$f$-$R$me(B /:|)

```

---

<div class="post-metadata">

**Author:** ![GOTOU\_Yuuzou](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/a88e4f/32.png) [@GOTOU\_Yuuzou](https://www.ruby-forum.com/u/GOTOU_Yuuzou)\
**Post date:** [December 24, 2007, 6:52pm UTC](https://www.ruby-forum.com/t/enumerable-cant-take-multiple-parameters/124086/3 "2007-12-24T18:52:41Z")

</div>

In article  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid),  
GOTOU Yuuzou [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) writes:

> e$B$H$$$&$N$O$J$s$H$J$/ITJX$J5$$,$9$k$N$G!"J#?t$N%Q%i%a!\<%?$r\<ue(B  
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e$B$?$H$($P!“e(Benum.max {|a, b| … } e$B$r$I$&Dj5A$9$k$+!”$H$+!#e(B

collect e$B$G$"$l$Pe(B

> In message “Re: [ruby-dev:32708] Enumerable can’t take multiple parameters”  
> on Mon, 24 Dec 2007 22:25:54 +0900, GOTOU Yuuzou [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) writes:

> module Enumerable  
> def collect  
> result = []  
> self.each{|\*x| result.push(yield \*x)}  
> result  
> end  
> end

e$B$H!“$”$kDxEY$O\<+A3$KDj5A$G$-$^$9$,!"e(Bmax e$B$rF1MM$KDj5A$9$k$N$Oe(B  
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e$B\<h$C$?$b$N$H$9$k$H$$$&$N$O$”$jF@$k$+$b$7$l$^$;$s!#e(B

---

<div class="post-metadata">

**Author:** ![GOTOU\_Yuuzou](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/a88e4f/32.png) [@GOTOU\_Yuuzou](https://www.ruby-forum.com/u/GOTOU_Yuuzou)\
**Post date:** [December 24, 2007, 6:38pm UTC](https://www.ruby-forum.com/t/enumerable-cant-take-multiple-parameters/124086/4 "2007-12-24T18:38:04Z")

</div>

In message [E1J6pjL-0004zA-0g@localhost](mailto:E1J6pjL-0004zA-0g@localhost),  
`Yukihiro M. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)’ wrote:

> |e$B$3$N1F6A$G!"e(BRSSe$B$N%F%9%H$,\<:GT$7$F$$$^$9!#e(B  
> |e$B$3$N%1!\<%9$G$Oe(BREXML::Elemenet#eache$B$r0J2\<$N$h$&$K=$@5$9$l$P4ue(B  
> |e$BK\>$9$kF0:n$K$J$j$^$9$,!"e(BEnumerablee$B$NLdBj$J$N$+e(Beache$B$r\<BAu$9$ke(B  
> |e$BB&$NLdBj$J$N$+H=CG$G$-$^$;$s$G$7$?!#e(B
> 
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def each  
@hash.each do |k, v|  
yield(k, v)  
end  
end

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- eache$B$@$1$O0U?^$7$?DL$j$KF0$$$F$7$^$&e(B
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e$B$H$$$&$N$O$J$s$H$J$/ITJX$J5$$,$9$k$N$G!"J#?t$N%Q%i%a!\<%?$r\<ue(B  
e$B$1\<h$k$N$,L5Fq$G$O$J$$$G$7$g$&$+!#e(B

---

<div class="post-metadata">

**Author:** ![GOTOU\_Yuuzou](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/a88e4f/32.png) [@GOTOU\_Yuuzou](https://www.ruby-forum.com/u/GOTOU_Yuuzou)\
**Post date:** [December 24, 2007, 10:11pm UTC](https://www.ruby-forum.com/t/enumerable-cant-take-multiple-parameters/124086/5 "2007-12-24T22:11:36Z")

</div>

In message [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid),  
`Tanaka A. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)’ wrote:

> In article [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid),  
> GOTOU Yuuzou [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) writes:
> 
> > e$B$H$$$&$N$O$J$s$H$J$/ITJX$J5$$,$9$k$N$G!"J#?t$N%Q%i%a!\<%?$r\<ue(B  
> > e$B$1\<h$k$N$,L5Fq$G$O$J$$$G$7$g$&$+!#e(B
> 
> e$BLdBj$O\<u$1\<h$C$?8e$K$I$&$9$k$+!"$G$O$J$$$G$7$g$&$+!#e(B
> 
> e$B$?$H$($P!“e(Benum.max {|a, b| … } e$B$r$I$&Dj5A$9$k$+!”$H$+!#e(B  
> (snip)  
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