Introduction

Pattern matching allows us to make different computation depending on matching pattern. It is very similar to Switch statement in c and c++. Its syntax is given below.

match exp with
| pattern1 -> result
| pattern2 -> result
|------------------
|------------------
| _ -> default

Now we write the code for getting day name by passing day number. Like following code.

let week n =
match n with

| 1 -> "Monday"
| 2 -> "Tuesday"
| 3 -> "Wednesday"
| 4 -> "Thursday"
| 5 -> "Friday"
| 6 -> "Saturday"
| 7 -> "Sunday"
| _-> "Wrong Input"

printfn "%s" (week 1)
printfn "%s" (week 2)
printfn "%s" (week 5)

printfn "%s" (week 9)

Output:

pattern matching in F#