Created
February 4, 2016 19:54
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Variable `counter` passed to a macros behaves as if it was passed by-reference.
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| scala> var c = 0 | |
| c: Int = 0 | |
| scala> inc(c) | |
| scala> c | |
| res1: Int = 1 |
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| def inc(counter: Int): Unit = macro incImpl | |
| def incImpl(c: Context)(counter: c.Expr[Int]): c.Expr[Unit] = { | |
| import c.universe._ | |
| c.Expr[Unit](q"$counter += 1") | |
| } |
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