Homework #1

[saucisson]

Homework #1 is available in README. It must be done before 20th march 2018 08:00.
I will add some tests during this week. Feel free to add your own tests.

[saucisson]

I have put an example of constant propagation for a subset of the abstract syntax tree. To do it, we had to update the anzen package. You must thus do the rm -rf .build Package.resolved command before swift test, in order to download the latest version.

[saucisson]

You have mainly to fill the code within semantique/Sources/semantique/PropagateConstantVisitor.swift for this homework.

[saucisson]

The tests i am using for this homework are:

    let test_expressions = [
        // Already a constant:
        """
        let x = 1
        """,
        // Expression on integers constants:
        """
        let x = 1 + 2 * 3 - 4
        """,
        // Expression using integer constants and a variable:
        """
        let x = 1
        let y = x + 2
        let z = -x + 2
        """,
        // Expression using a variable with no value:
        """
        let x = 1
        let y : Int
        let z = x + y
        """,
        // Expression on Boolean values and variables:
        """
        var x = true
        x = x and false
        """,
        // Expression on string values and variables:
        """
        let x = "abcdef"
        let y = x
        """,
        // Condition:
        """
        var x = 2
        var y = 2
        if x == y {
          y = x
        } else {
          x = y
        }
        """,
        // Function declaration and call:
        """
        let x = 2
        fun f(_ a: Int) -> Int {
          return a * x
        }
        let y = f(x) * x
        """,
        // Function declaration and call:
        """
        var x = 2
        fun f(_ a: Int) -> Int {
          return a * x
        }
        let y = f(x) * x
        """,
    ]

[saucisson]

Grades have been pushed into your repositories, under branch homework-1. Please check them.