Add lecture 6

Author: VaclavMacha

docs_vitepress/make.jl

@@ -56,11 +56,11 @@ pages = [
             "Lab" => "lab.md",
             "Homework" => "hw.md",
         ]),
-        # "6: Lanuage introspection" => add_prefix("lecture_06", [
-        #     "Lecture" => "lecture.md",
-        #     "Lab" => "lab.md",
-        #     "Homework" => "hw.md",
-        # ]),
+        "6: Lanuage introspection" => add_prefix("lecture_06", [
+            "Lecture" => "lecture.md",
+            "Lab" => "lab.md",
+            "Homework" => "hw.md",
+        ]),
         "7: Macros" => add_prefix("lecture_07", [
             "Lecture" => "lecture.md",
             "Lab" => "lab.md",

docs_vitepress/src/lectures/lecture_06/hw.md

@@ -0,0 +1,48 @@
+# Homework 6: Find variables
+
+Following the lab exercises, you may think that metaprogramming is a fun little exercise. Let's challenge this notion in this homework, where *YOU* are being trusted with catching all the edge cases in an AST.
+
+## How to submit?
+
+Put the code of the compulsory task inside `hw.jl`. Zip only this file (not its parent folder) and upload it to BRUTE. Your file should not use any 3rd party dependency.
+
+::: danger Homework (2 points)
+
+Your task is to find all single letter variables in an expression, i.e. for example when given expression
+
+```julia
+x + 2*y*z - c*x
+```
+
+return an array of *unique alphabetically sorted symbols* representing variables in an expression.
+
+```julia
+[:c, :x, :y, :z]
+```
+
+Implement this in a function called `find_variables`. Note that there may be some edge cases that you may have to handle in a special way, such as 
+
+- variable assignments `r = x*x` should return the variable on the left as well (`r` in this case)
+- ignoring symbols representing single letter function calls such as `f(x)`
+
+:::
+
+::: details Show solution
+
+Nothing to see here.
+
+:::
+
+# Voluntary exercise
+
+::: danger Voluntary exercise
+
+Create a function that replaces each of `+`, `-`, `*` and `/` with the respective checked operation, which checks for overflow. E.g. `+` should be replaced by `Base.checked_add`.
+
+:::
+
+::: details Show solution
+
+Not yet published.
+
+:::