fun task ← void by text about, fun code
  writeLine(0U00b7, " ", about)
  code()
end
fun answer ← void by var message do writeLine("  ", message) end
# few definitions
fun noArgumentsFunction ← int by block do return 97 end
fun fixedArgumentsFunction ← void by var a, var b do end
fun variadicFunction ← void by text a, some var values do end
fun funArgumentFunction ← var by fun f, var b do return f() + b end
task("Calling a function that requires no arguments", void by block
  answer("Is supported.")
  noArgumentsFunction()
end)
task("Calling a function with a fixed number of arguments", void by block
  answer("Is supported.")
  fixedArgumentsFunction(97, 3.14)
end)
task("Calling a function with optional arguments", void by block
  answer("Not supported in EMal.")
end)
task("Calling a function with a variable number of arguments", void by block
  answer("Variadic functions are supported.")
  variadicFunction("mandatory", 97, 3.14)
  variadicFunction("mandatory", 97)
end)
task("Calling a function with named arguments", void by block
  answer("Not supported in EMal.")
end)
task("Using a function in statement context", void by block
  answer("Is supported.")
  if true do noArgumentsFunction()
  else do fixedArgumentsFunction(97, 3.14) end
end)
task("Using a function in first-class context within an expression", void by block
  answer("Functions are first class, can be passed as arguments and returned.")
  answer(funArgumentFunction(noArgumentsFunction, 3.14))
end)
task("Obtaining the return value of a function", void by block
  answer("Is supported.")
  int value ← noArgumentsFunction()
  answer(value)
end)
task("Distinguishing built-in functions and user-defined functions", void by block
  answer("No distinction.")
end)
task("Distinguishing subroutines and functions", void by block
  answer("No distinction, we support void return type.")
end)
task("Stating whether arguments are passed by value or by reference", void by block
  answer("Pass by value, but text, blob, objects hold a reference.")
end)
task("Is partial application possible and how", void by block
  answer("Is supported.")
  ^|I had some confusion about partial application and currying, thanks to these links:
   |  https://stackoverflow.com/questions/218025/what-is-the-difference-between-currying-and-partial-application
   |  https://web.archive.org/web/20161023205431/http://www.uncarved.com/articles/not_curryin
   |^
  # Partial applying
  fun add ← int by int a, int b do return a + b end
  fun partial ← fun by fun f, int a
    return int by int b
      return add(a, b)
    end
  end
  fun add7 ← partial(add, 7)
  answer(add(7, 5))
  answer(add7(5))
  # Currying
  fun addN ← fun by int n
    return int by int x
      return x + n
    end
  end
  fun plus ← int by int a, int b
    fun addA ← addN(a)
    return addA(b)
  end
  answer(plus(7, 5))
end)