[#41916] Proposal: Bitmap Marking GC — Narihiro Nakamura <authornari@...>

Hi.

18 messages 2012/01/05

[#41941] [ruby-trunk - Bug #5851][Open] make check fails when compiling with GCC 4.7 - *** longjmp causes uninitialized stack frame *** — Vit Ondruch <v.ondruch@...>

12 messages 2012/01/06

[#41979] [ruby-trunk - Bug #5865][Open] Exception#== should return false if the classes differ — Hiro Asari <asari.ruby@...>

10 messages 2012/01/08

[#42003] [ruby-trunk - Bug #5871][Open] regexp \W matches some word characters when inside a case-insensitive character class — Gareth Adams <gareth@...>

14 messages 2012/01/09

[#42016] [ruby-trunk - Feature #5873][Open] Adopt FFI over DL — Heesob Park <phasis@...>

15 messages 2012/01/10

[#42149] [ruby-trunk - Feature #5899][Open] chaining comparsions. — Ondrej Bilka <neleai@...>

12 messages 2012/01/16

[#42164] [ruby-trunk - Feature #5903][Open] Optimize st_table (take 2) — Yura Sokolov <funny.falcon@...>

18 messages 2012/01/17

[ruby-core:42289] Re: [ruby-trunk - Bug #5663][Open] Combined map/select method

From: Roger Pack <rogerdpack2@...>
Date: 2012-01-31 17:47:24 UTC
List: ruby-core #42289
> It is pretty common to want to map over an Enumerable, but only include the elements that match a particular filter. A common idiom is:
>
> enum.map { |i| i + 1 if i.even? }.compact
>
> It is of course also possible to do this with two calls:
>
> enum.select { |i| i.even? }.map { |i| i + 1 }
>
> Both cases are clumsy and require two iterations through the loop. I'd like to propose a combined method:


+1 for a combined map and select.  I find myself reaching for it every
so often and wishing it were there.

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