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54 lines
1.3 KiB
Markdown
54 lines
1.3 KiB
Markdown
/*
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Set yourself up:
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1) Download Scala - http://www.scala-lang.org/downloads
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2) unzip/untar in your favourite location and put the bin subdir on the path
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3) Start a scala REPL by typing scala. You should see the prompt:
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scala>
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This is the so called REPL. You can run commands in the REPL. Let do just that:
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*/
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println(10) // prints the integer 10
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println("Boo!") // printlns the string Boo!
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// Evaluating a command gives you the type and value of the result
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1 + 7
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/* The above line results in:
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scala> 1 + 7
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res29: Int = 8
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This means the result of evaluating 1 + 7 is an object of type Int with a value of 8
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1+7 will give you the same result
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*/
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// Everything is an object, including a function type these in the repl:
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7 // results in res30: Int = 7 (res30 is just a generated var name for the result)
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// The next line gives you a function that takes an Int and returns it squared
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(x:Int) => x * x
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// You can assign this function to an identifier, like this:
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val sq = (x:Int) => x * x
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/* The above says this
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sq: Int => Int = <function1>
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Which means that this time we gave an explicit name to the value - sq is a function that take an Int and returns Int.
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sq can be executed as follows:
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*/
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sq(10) // Gives you this: res33: Int = 100. The result is the Int with a value 100
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