Differences

This shows you the differences between two versions of the page.

--- cs330_f2016:lab16judgments [2016/12/02 04:49]
morse created
+++ cs330_f2016:lab16judgments [2021/06/30 23:42]
@@ Line 1: / Line 1: @@
-==== Type Judgments for the Type Checking Lab ====
-Here are the type judgments we went over in class translated into English form instead of the notation we used in class:
-* numeric literal: always results in a number
-* boolean literal (true / false): always results in a boolean
-* addition / subtraction: if both are numbers, results in a number
-* iszero: if input is a number, result is a boolean
-* id: look it up in the type environment to find out its type
-* with: results in the type resulting from the body after adding to the type environment that the type of the identifier is the type of the initialization expression
-* if: if the type of the conditional is boolean and the types of the two possible branches are the same, results in the type of either branch
-* lambda: results in a function from the declared type of the input parameter to the return type of the body after adding to the type environment that the formal parameter is the declared type
-* app: if the operator is a function (t1 -> t2), and if the type of the actual parameter is type t1, results in type t2.

BYU CS classes