- Ordering using andThen: f(x) andThen g(x) = g(f(x))
- Ordering using compose: f(x) compose g(x) = f(g(x))
println("Step 1: Assume a pre-calculated total cost amount")
val totalCost: Double =
println("\nStep 2: How to define a val function to apply discount to total cost")
val applyDiscountValFunction = (amount: Double) => {
println("Apply discount function")
val discount = // fetch discount from database
amount - discount
}
println("\nStep 3: How to call a val function")
println(s"Total cost of 5 donuts with discount = ${applyDiscountValFunction(totalCost)}")
println("\nStep 4: How to define a val function to apply tax to total cost")
val applyTaxValFunction = (amount: Double) => {
println("Apply tax function")
val tax = // fetch tax from database
amount + tax
}
println("\nStep 5: How to call andThen on a val function")
println(s"Total cost of 5 donuts = ${ (applyDiscountValFunction andThen applyTaxValFunction)(totalCost) }")result:
Step : Assume a pre-calculated total cost amount Step : How to define a val function to apply discount to total cost Step : How to call a val function
Apply discount function
Total cost of donuts with discount = Step : How to define a val function to apply tax to total cost Step : How to call andThen on a val function
Apply discount function
Apply tax function
Total cost of donuts =