Short for String.format in Scala
Is there a short syntax for string interpolation in Scala? So开发者_开发技巧mething like:
"my name is %s" < "jhonny"
Instead of
"my name is %s" format "jhonny"
No, but you can add it yourself:
scala> implicit def betterString(s:String) = new { def %(as:Any*)=s.format(as:_*) }
betterString: (s: String)java.lang.Object{def %(as: Any*): String}
scala> "%s" % "hello"
res3: String = hello
Note that you can't use <
, because that would conflict with a different implicit conversion already defined in Predef.
In case you are wondering what syntax may be in the works
$ ./scala -nobootcp -Xexperimental
Welcome to Scala version 2.10.0.r25815-b20111011020241
scala> val s = "jhonny"
s: String = jhonny
scala> "my name is \{ s }"
res0: String = my name is jhonny
Playing some more:
scala> "those things \{ "ne\{ "ts".reverse }" }"
res9: String = those things nest
scala> println("Hello \{ readLine("Who am I speaking to?") }")
Who am I speaking to?[typed Bozo here]Hello Bozo
I seem to remember Martin Odersky having been quoted with stating that string concatenation in the style presented in "Programming in Scala" is a useful approximation to interpolation. The idea is that without spaces you are only using a few extra characters per substitution. For example:
val x = "Mork"
val y = "Ork"
val intro = "my name is"+x+", I come from "+y
The format method provides a lot more power however. Daniel Sobral has blogged on a regex based technique too.
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