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scalastring-interpolation

scala string interpolation inject value dynamically

I have two strings:

val s1: String = "aaa/$Y/$m/aaa_$Y$m$d" // this one has all three variables
val s2: String = "aaa/$Y/$m" // this one has only two variables

val myStrings: Seq[String] = Seq(s1, s2)

val myStringsUpdated: Seq[String] = myStrings.map(s => ???)

Can I inject Y, m, d values into s1, s2 dynamically so I get myStringsUpdated sequence?

Solution

  • As Tim already mentioned interpolation is done at compile-time, so you can't use it directly, but you could do a simple trick and wrap it into function:

    //instead of plain interpolated string we've got function returning interpolated string
def s1(Y: String, m: String, d: String): String = s"aaa/$Y/$m/aaa_$Y$m$d" 
def s2(Y: String, m: String, d: String): String = s"aaa/$Y/$m" 

val myStrings: Seq[(String, String, String) => String] = Seq(s1, s2)

//you inject value by just applying function
val myStringsUpdated = myStrings.map(_.apply("1999", "11", "01"))

println(myStringsUpdated) //List(aaa/1999/11/aaa_19991101, aaa/1999/11)