Tables.kt

fun <T1, T2> table(body: (T1, T2) -> Unit): TableBuilder2<T1, T2> {
  return TableBuilder2(body)
}

fun <T1, T2, T3> table(body: (T1, T2, T3) -> Unit): TableBuilder3<T1, T2, T3> {
  return TableBuilder3(body)
}

class TableBuilder2<T1, T2>(private val tableBody: (T1, T2) -> Unit) {
  infix fun where(whereBody: RowBuilder.() -> Unit) {
    RowBuilder().whereBody()
  }

  inner class RowBuilder {
    fun row(col1: T1, col2: T2) = tableBody.invoke(col1, col2)
  }
}

class TableBuilder3<T1, T2, T3>(private val tableBody: (T1, T2, T3) -> Unit) {
  infix fun where(whereBody: RowBuilder.() -> Unit) {
    RowBuilder().whereBody()
  }

  inner class RowBuilder {
    fun row(col1: T1, col2: T2, col3: T3) {
      tableBody.invoke(col1, col2, col3)
    }
  }
}

TableSpec.kt

import org.jetbrains.spek.api.Spek

class TableSpec : Spek({
  describe("using a table") {
    table { a: String, b: Int ->
      describe("$a and $b are parameters") {
        it("should work") {
          assert(a is String)
          assert(b is Int)
        }
      }
    } where {
      row("foo", 1)
      row("bar", 2)
    }
  }

  table { a: Int, b: Int, c: Int ->
    it("adds up $a and $b to equal $c") {
      assert(a + b == c)
    }
  } where {
    row(1, 2, 3)
    row(4, 6, 10)
  }
})