# \[Feature:trunk\] enhancement of Array#drop

**URL:** <https://www.ruby-forum.com/t/feature-trunk-enhancement-of-array-drop/168293>\
**Category:** Development\
**Created:** [May 19, 2009, 8:59am UTC](https://www.ruby-forum.com/t/feature-trunk-enhancement-of-array-drop/168293 "2009-05-19T08:59:17Z")\
**Posts on this page:** 7\
**Page:** 1

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [May 19, 2009, 8:59am UTC](https://www.ruby-forum.com/t/feature-trunk-enhancement-of-array-drop/168293/1 "2009-05-19T08:59:17Z")

</div>

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e$BL5\>r7o$G@hF,$NMWAG$r:o=|$9$k%a%=%C%I$H$7$F$Oe(Bshifte$B$^$?$Oe(Bdrop(1)  
e$B$,$"$j!"$^$?!"\>r7o$K9gCW$7$?A4$F$NMWAG$r:o=|$9$k%a%=%C%I$H$7e(B  
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…  
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e$BNce(B:  
[:a, :b, :a, :b].drop(1){|e| e == :b} #=\> [:a, :a, :b]  
[:a, :b, :a, :b].drop(2){|e| e == :b} #=\> [:a, :a]

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e$BBhe(B2e$B0z?te(B} e$B$H$\_$Je(B  
e$B$9$h$&$K$9$l$P$5$i$KJXMx!”$H$b8@$o$l$^$7$?!#e(B

e$BNce(B:  
[:a, :b, :a, :b].drop(1, :b) #=\> [:a, :a, :b]

e$B;d$H$7$F$O$3$N;EMM$,\<B8=$5$l$k$HBgJQJXMx$H;W$&$N$G$9$,!"$$$+e(B  
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---

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [May 19, 2009, 9:20am UTC](https://www.ruby-forum.com/t/feature-trunk-enhancement-of-array-drop/168293/2 "2009-05-19T09:20:59Z")

</div>

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

In message “Re: [ruby-dev:38493] [Feature:trunk] enhancement of  
Array#drop”  
on Tue, 19 May 2009 15:58:46 +0900, “U.Nakamura”  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) writes:

|Rubye$B$G%9%/%j%W%H$r=q$$$F$$$F!“G[Ns$+$i!”$"$k\>r7o$K9gCW$9$k@he(B  
|e$BF,$NMWAG$N$_$r:o=|$9$k!“$H$$$&=hM}$r=q$-$?$$\>lLL$K=P2q$C$?$3e(B  
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|  
|e$BL5\>r7o$G@hF,$NMWAG$r:o=|$9$k%a%=%C%I$H$7$F$Oe(Bshifte$B$^$?$Oe(Bdrop(1)  
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|e$B$F$Oe(Bdeletee$B$,$”$j$^$9$,!“$”$k\>r7o$K9gCW$9$k@hF,$NMWAG$N$_$r:oe(B  
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|  
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|e$B%/0z?t$rDI2C$9$k$N$O$I$&$+!W$H8@$o$l$^$7$?!#e(B

drop\_whilee$B$H$O0c$&$N$G$9$M!#e(B

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---

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [May 19, 2009, 5:07pm UTC](https://www.ruby-forum.com/t/feature-trunk-enhancement-of-array-drop/168293/3 "2009-05-19T17:07:36Z")

</div>

e$B$3$s$K$A$O!"$J$+$`$ie(B(e$B$&e(B)e$B$G$9!#e(B

In message “[ruby-dev:38495] Re: [Feature:trunk] enhancement of  
Array#drop”  
on May.19,2009 16:20:07, [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote:  
| |Rubye$B$G%9%/%j%W%H$r=q$$$F$$$F!“G[Ns$+$i!”$"$k\>r7o$K9gCW$9$k@he(B  
| |e$BF,$NMWAG$N$_$r:o=|$9$k!“$H$$$&=hM}$r=q$-$?$$\>lLL$K=P2q$C$?$3e(B  
| |e$B$H$,2?EY$+$”$j$^$9!#e(B  
| |  
| |e$BL5\>r7o$G@hF,$NMWAG$r:o=|$9$k%a%=%C%I$H$7$F$Oe(Bshifte$B$^$?$Oe(Bdrop(1)  
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| |  
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| |e$B%/0z?t$rDI2C$9$k$N$O$I$&$+!W$H8@$o$l$^$7$?!#e(B  
|  
| drop\_whilee$B$H$O0c$&$N$G$9$M!#e(B

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e$B$=$l$G$O!#e(B

---

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [May 19, 2009, 6:20pm UTC](https://www.ruby-forum.com/t/feature-trunk-enhancement-of-array-drop/168293/4 "2009-05-19T18:20:52Z")

</div>

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

> > [:a, :b, :a, :b].drop(1){|e| e == :b} #=\> [:a, :a, :b]  
> > [:a, :b, :a, :b].drop(2){|e| e == :b} #=\> [:a, :a]
> 
> e$B$@$=$&$G$9$+$i!"$3$l$O!V0z?t$G;XDj$7$?HO0OFb$G\>r7o$rK~$?$9MWe(B  
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> e$B$3$C$A$J$s$G$9$+!)e(B

e$B$3$l$O!"e(B

drop one element which equals :b  
drop two elements which equals :b

e$B$HFI$`$s$8$c$J$$$G$9$+$M$'!#e(B

e$B$\*$=$i$/!#e(B

---

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [May 19, 2009, 6:06pm UTC](https://www.ruby-forum.com/t/feature-trunk-enhancement-of-array-drop/168293/5 "2009-05-19T18:06:04Z")

</div>

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

In message “Re: [ruby-dev:38500] Re: [Feature:trunk] enhancement of  
Array#drop”  
on Wed, 20 May 2009 00:06:19 +0900, “U.Nakamura”  
[removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) writes:

|| drop\_whilee$B$H$O0c$&$N$G$9$M!#e(B  
|  
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|e$B$&$G$9!#e(B

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e$B:o=|$9$k!W$G$9!#e(BRDoce$B$+$iNcBj$r0zMQ$9$k$He(B

```
a = [1, 2, 3, 4, 5, 0]
a.drop_while {|i| i < 3 } # => [3, 4, 5, 0]

```

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> [:a, :b, :a, :b].drop(1){|e| e == :b} #=\> [:a, :a, :b]  
> [:a, :b, :a, :b].drop(2){|e| e == :b} #=\> [:a, :a]

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```
                            e$B$^$D$b$He(B e$B$f$-$R$me(B /:|)

```

---

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [May 21, 2009, 9:15pm UTC](https://www.ruby-forum.com/t/feature-trunk-enhancement-of-array-drop/168293/6 "2009-05-21T21:15:40Z")

</div>

e$B%A%1%C%He(B #1492 e$B$,99?7$5$l$^$7$?!#e(B (by Yukihiro M.)

e$B%9%F!\<%?%9e(B Opene$B$+$ie(BClosede$B$KJQ99e(B

## redundant

[http://redmine.ruby-lang.org/issues/show/1492](http://redmine.ruby-lang.org/issues/show/1492)

---

<div class="post-metadata">

**Author:** ![U.Nakamura](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/u/b5ac83/32.png) [@U.Nakamura](https://www.ruby-forum.com/u/U.Nakamura)\
**Post date:** [May 19, 2009, 6:50pm UTC](https://www.ruby-forum.com/t/feature-trunk-enhancement-of-array-drop/168293/7 "2009-05-19T18:50:21Z")

</div>

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

In message “Re: [ruby-dev:38505] Re: [Feature:trunk] enhancement of  
Array#drop”  
on Wed, 20 May 2009 01:19:11 +0900, Tanaka A. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)  
writes:

|\>\> [:a, :b, :a, :b].drop(1){|e| e == :b} #=\> [:a, :a, :b]  
|\>\> [:a, :b, :a, :b].drop(2){|e| e == :b} #=\> [:a, :a]  
|\>  
|\> e$B$@$=$&$G$9$+$i!"$3$l$O!V0z?t$G;XDj$7$?HO0OFb$G\>r7o$rK~$?$9MWe(B  
|\> e$BAG$r:o=|$9$k!W%a%=%C%I$K$J$C$F$$$^$9!#$&$5$5$s$N$[$7$$$b$N$Oe(B  
|\> e$B$3$C$A$J$s$G$9$+!)e(B  
|  
|e$B$3$l$O!"e(B  
|  
| drop one element which equals :b  
| drop two elements which equals :b  
|  
|e$B$HFI$`$s$8$c$J$$$G$9$+$M$'!#e(B

e$B$_$_!#$=$s$JFI$\_J}$,!#e(B

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