Issue #7300 has been updated by knu (Akinori MUSHA).


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?????????å­???????nil??ªã????¦å???????¦ã????£ã???????³ã?¼ã????£ã?³ã?°ã????¹ã?ªã?®ã?§ã??è­¦å???????ºã????????????ªã??ä¾?å¤??????ºã????¦ç?´ã??????????¹ã???????¨æ???????¾ã?????

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Hash[enum.map {|x| x > 0 ? [x, x*x] : nil }]
??®ã???????«å???????«ã??????·ã?¥ã??ä½??????¨ã????«æ???³ç?????nilï¼????????????¯é??????????§ã????ªã??ä»»æ???®å?¤ï?????使ã?£ã?¦ã????¢ã?®ç??????????¹ã?­ã?????????????´å????§ã??????????????
????????«ã????¦ã??????????ªä??æ§???¯æ???????????示ã???????¦ã????ªã????®ã?§ã???????????æ©???«ç?´ã????¦ã??????????®ã????????æ°?????????¾ã????????Hash[?????§æ??ç´¢å?½ã????????

Hash[enum.map {|x| x > 0 ? [x, x*x] : nil }.compat] # minimum change
Hash[enum.flat_map {|x| x > 0 ? [x, x*x] : [] }] # 1.9+ only
{}.tap { |h| enum.each {|x| x > 0 and h[x] = x*x } }

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Bug #7300: Hash#[] ??®æ???????? 1.9.3 ??¨ç?°ã?ªã?£ã?¦ã?????
https://bugs.ruby-lang.org/issues/7300#change-32547

Author: hsbt (Hiroshi SHIBATA)
Status: Open
Priority: Normal
Assignee: 
Category: core
Target version: 2.0.0
ruby -v: ruby 2.0.0dev (2012-11-07) [x86_64-darwin12.2.0]


Hash[[nil]] ???å®?è¡?????????? 1.9.3 ??§ã?? {} ??¨ã?ªã???????®ã?? 2.0.0 ??§ã?? ArgumentError ??¨ã?ªã????¾ã?????

??ªã?????????????«ç?¸è???????¦ã?¿ã????????2.0.0 ??®å????????ä¸?æ­£ã?ªã????®ã???????§ã????¯ã????¦ã?¦æ­£???????????????
???????????¨ã??????????¦ã??????????¾ã???????????2.0.0 ??§ã?? dupricate ??®è­¦???????????«ã????¦ã??
次ã?®ã?ªã?ªã?¼ã?¹ã?§æ???????¨ã???????¹ã????¯ã??????????«æ???????¾ã?????


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