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SCALA
2018-11-10
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• #&"%$"
• Java 17Scala 3
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Yohei TSUJI
@crossroad0201
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implicit class
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163'JRNF6
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case class
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case class
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sealed 2/65')
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flatten()
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map()
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flatMap()
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fold() (1/2)
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fold() (2/2)
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foldLeft() / foldRight()
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,24$Either
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&/;?.-
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= DE C CC .E C = ?E
D = DD . DE CC C FD :C = E ? D CC C
D = DD = E ? CC C E =D . B CC C E = E ? D CC C
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• /;?%'23506=?2. ! "
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#& %$%Either!&%"
? B A B A E E )))
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• #& sealed
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Java
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Java'6G<(!.
• Scala6G<'&Java6G<-)%,&Java&!.6G<()!
• null
• 6E47BF
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null
Option
=15 55/15 2) . :4 3 (
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• null Option( ) NULL
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Scala%19027:$,
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• Java%19027:
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)Try$3$Either'
0 (1/3)
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Try Either (2/3)
> F C F L
= C = =F EE ,CE ( C = F ( ( JF A E A L
: F ( ( , ( : < ( , (=F< ( , ( L
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TryEither
(3/3)
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: = A_) , = A
= : _ _ A = A( _,A : _ :A . = _ = A/_ _
E_
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_A=,E A =
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H@=?>,ScalaTest6
> DFi D F: F L > :A =:A =:A"i A > :"i. F =:D "i D : M
i GAF : >F DK A.: DK :
: F:A i D : iI>F=i > :A =:A =:A
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Scalaz : Cats 45>/";
Scala0GMCJHNC@
*=,84JAFJK#?>='1#<7*#
GMCJHNC3>=705
0)2 6!# 1 7*
7+5Scala4JAFJK0(>/ = DLBEINOptionTryEither @
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'>;@)/<2%2./$,; Scalaz : Cats 4@*=1 1 7
*
• Scalaz: https://github.com/scalaz/scalaz
• Cats: https://github.com/typelevel/cats
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IDE.IntelliJ IDEA3
• IntelliJ IDEA: https://www.jetbrains.com/idea/
• JetBrains
- Scala Plugin )%
https://plugins.jetbrains.com/plugin/1347-scala
• +7J?
• !2+8I:;59A4F4>
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• Scala-),.- Community Edition )0 )%
• &-%%/DF64I.#(10
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IntelliJ IDEA%%/DF64I: https://qiita.com/crossroad0201/items/bf5528cc57cadab67638
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$ !$"$
• $ !$"$ $
• Scalafmt: https://github.com/scalameta/scalafmt
#
• Scalariform: https://github.com/scala-ide/scalariform
• scalafmt:
https://speakerdeck.com/norinori3/scalafmtnituitediao-hetemita
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-2
• The Scala Programming Language: https://www.scala-lang.org/
• %12Scala "!$: https://dwango.github.io/scala_text/
• Effective Scala: http://twitter.github.io/effectivescala/index-ja.html
• Scala*+: http://www.ne.jp/asahi/hishidama/home/tech/scala/
• Scala!3,'.(0,)2
3: http://amzn.asia/d/f56DXon
• Scala: http://amzn.asia/d/1TQ38iG
• Scala
/ &: http://amzn.asia/d/7igHuwm
• Scala#2&(0,)2: http://amzn.asia/d/hgUMwzq
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!
HAVE A GOOD
SCALA LIFE !!
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