info/teamwork.md

+To monitor fair division of work in your groups, we ask that each of you sends us an _individual_ email, from your EPFL address, to both PhD assistants and the instructor via **email**.
+The email should contain an estimate how much you and your team mates contributed to each of the four common projects and to the self-chosen final project, with * next to your name, in the form of a table with percentages rounded down, e.g., with a perfect split:
+
+Person1 Lab1:33%, Lab2:33%, Lab3:33%, Lab4:33%, Lab5: 33%, Project: 33%
+Person2* Lab1:33%, Lab2:33%, Lab3:33%, Lab4:33%, Lab5: 33%, Project: 33%
+Person3 Lab1:33%, Lab2:33%, Lab3:33%, Lab4:33%, Lab5: 33%, Project: 33%
+
+Every column should add to 99 or 100; if you each repeated the same work (e.g. each of you solved Lab1 entirely on your own but only one solution was taken), please renormalize and devide "redundantly" done work evenly.
+
+After that, please add any specific clarifications and explanations _if_ you feel it is helpful, but try to keep them no longer than 10 sentences.
+
+We leave it to each of you whether you discuss and reconcile these numbers and claims within the group. In any case, we would like to receive emails from _individual_ students, without CC or BCC to the remaining group members. Hence, in some cases we may see contradictory information if that reflects how people feel. The email title should be "My Teamwork Statement CS-320". If you have any issues or questions regarding this, please ask here on Ed, or directly to the same emails (but a clarification email should have a somewhat different title, like "Question on Teamwork Statement").
+
+If we get nearly 33% for everything from every group member of a 3-person group (with or without explanations), we will trust this group did a fair split and leave it at that. Else, we may follow up with you in the following weeks. We will try to use this information in a positive way, and we hope that this final step will not ruin any otherwise working group dynamics.
+
+We ask you to submit teamwork statements twice:
+  * on the day after the deadline for Lab 3
+  * on the day after the deadline for the final lab (extension project)
+  

labs/amy_reference_compiler.md

-# The Amy Reference Compiler
-
-We provide you with a reference compiler for the Amy language that you can use to explore the expected behavior of your own compiler.
-
-The reference compiler is [available here](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/amyc-assembly-1.7.jar).
-
-You can run it as follows:
-  java -cp amyc-assembly-1.7.jar amyc.Main [options] [input files]
-
-To see the list of available options do 
-  java -cp amyc-assembly-1.7.jar amyc.Main --help
-
-The easiest way to execute a program is to run it in `--interpret` mode. If you want to generate WebAssembly binary code, you should follow these steps:
-  * Install `nodejs`. We have tested amyc with Node version 12, though other versions might work. See the [Node website](https://nodejs.org/en/) for installation instructions.
-  * Make sure the `wat2wasm` executable is visible, i.e., it is in the system path or, for Linux or Mac, you are at the toplevel of the `amyc` directory.
-  * Run `npm install deasync` in the directory you plan to run `amyc`.
-  * Run `amyc` without options. You will get a few output files.
-  * Run `nodejs <output file>.js`
-
-
-# Bug Reports
-
-We welcome bug reports! Please use the forum on Moodle for this purpose.

labs/amy_specification.md

-# The Amy Specification 
-
-You can access the Amy specification document [here](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/amy_specification.pdf).

labs/labs_01.md

-Below you will find the instructions for the first lab assignment in which you will get to know and implement an interpreter for the Amy language. If you haven't looked at the [Labs Setup](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/labs_setup.md) page yet, please do so before starting out with the assignment.
-
-
-# Part 1: Your first Amy programs
-
-Write two example Amy programs each and make sure you can compile them using the [Amy Reference Compiler](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/amy_reference_compiler.md). Put them under `/examples`. Please be creative when writing your programs: they should be nontrivial and not reproduce the functionality of the examples in the `/library` and `/examples` directories of the repository. Of course you are welcome to browse these directories for inspiration.
-
-Remember that you will use these programs in the remaining of the semester to test your compiler, so don't make them too trivial! Try to test many features of the language.
-
-If you have questions about how a feature of Amy works, you can always look at the [Amy Specification](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/amy_specification.md). It's a good idea to keep a local copy of this document handy -- it will be your reference for whenever you are asked to implement an aspect of the Amy language throughout this semester.
-
-
-# Part 2: An Interpreter for Amy 
-
-The main task of the first lab is to write an interpreter for Amy. 
-
-(If you haven't been assigned your repository yet, you can download a packaged version of the interpreter lab's skeleton [here](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/labs01_material/clp-lab01.zip). If you already have your repository assigned, you can simply check out the `lab01` branch. Note that future labs will only be distributed through the repository, so be sure to familiarize yourself with the setup.)
-
-
-## Interpreters 
-
-The way to execute programs you have mostly seen so far is compilation to some kind of low-level code (bytecode for a virtual machine such as Java's; native binary code in case of languages such as C). An alternative way to execute programs is interpretation. According to Wikipedia, "an interpreter is a computer program that directly executes, i.e. performs, instructions written in a programming or scripting language, without previously compiling them into a machine language program". In other words, your interpreter is supposed to directly look at the code and *interpret* its meaning. For example, when encountering a call to the 'printString' function, your interpreter should print its argument on the standard output.
-
-## The general structure of the Interpreter 
-
-The skeleton of the assignment is provided by us in three files:
-
-- The `Main.scala` source file
-
-- The `Interpreter.scala` source file, and
-
-- the `amyc-frontend-1.7.jar` bytecode file, which is located under `lib/` .
-
-Now let's look into the code in a little more detail.
-
-In `Main.scala`, take a look at the main method, which is the entry point to your program. After processing the command line arguments of the interpreter, the main method creates a Pipeline, which contains the different stages of the compiler (more on it in later assignments). The Pipeline will first call the Amy frontend, which will parse the source program into an abstract syntax tree (AST) and check it for correctness according to the [Amy specification](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/amy_specification.md), and then passes the result to the Interpreter.
-The implementation of the frontend is given to you in compiled form, because you will need to write your own version in the next assignments. **Note**: You are only allowed to use this binary code to link against your interpreter.
-
-So what is this AST we've mentioned? For the computer to "understand" the meaning of a program, it first has to transform it from source (text) form to a more convenient form, which we call an abstract syntax tree. The AST abstracts away uninteresting things of the program (e.g. parentheses, whitespace, operator precedence...) and keeps the essential structure of the program. 
-
-In Scala, we represent the AST as a tree-form object. The tree has different types of nodes, each one representing a different programming structure. The types of nodes are of course represented as different classes, which all inherit from a class called Tree. Conveniently enough, the classes correspond pretty much one-to-one to the rules of the BNF grammar given in the language specification. E.g. in the language spec we read that a module looks as follows:
-
-Module ::= **object** Id Definition* Expr? **end** Id
-
-and indeed in the implementation we find a class 
-
-`case class ModuleDef(name: Identifier, defs: List[ClassOrFunDef], optExpr: Option[Expr]) extends Definition`
-
-You can find the source code of the AST [here](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/labs01_material/SymbolicTreeModule.scala).
-Note: This is not exactly the code we will use in later assignments, but it's good enough to serve as a reference while implementing this first assignment.
-
-
-## The Interpreter class
-
-Now let's delve into `Interpreter.scala`. This file currently only contains a partial implementation, and it is your task to complete it! The entrypoint into the interpreter is `interpret`, which takes an expression as input and executes its meaning. The main loop at the end of the class will just take the modules in order and interpret their expression, if present.
-
-`interpret` returns a `Value`, which is a type that represents a value that an Amy expression can produce. Value is inherited by classes which represent the different types of values present in Amy (`Int(32)`, `Booleans`, `Unit`, `String` and ADT values). `Value` has convenience methods to cast to `Int(32)`, `Boolean` and `String` (`as*`). Remember we can always call these methods safely when we know the types of an expression (e.g. the operands of an addition), since we know that the program type-checks.
-
-`interpret` takes an additional implicit parameter as an argument, which is a mapping from variables to values (in the interpreted language). In Scala, when an implicit parameter is expected, the compiler will look in the scope for some binding of the correct type and pass it automatically. This way we do not have to pass the same mapping over and over to all recursive calls to `interpret`. Be aware, however, that there are some cases when you need to change the `locals` parameter! Think carefully about when you have to do so.
-
-A few final notes:
-
-  * You can print program output straight to the console.
-  * You can assume the input programs are correct. This is guaranteed by the Amy frontend. 
-  * To find constructors and functions in the program, you have to search in the `SymbolTable` passed along with the program. To do this, use the three helper methods provided in the interpreter:
-    * `isConstrutor` will return whether the `Identifier` argument is a type constructor in the program
-    * `findFunctionOwner` will return the module which contains the given `Identifier`, which has to be a function in the program. E.g. if you give it the `printInt` function of the `Std` module, you will get the string `"Std"`.
-    * `findFunction` will return the function definition given a pair of Strings representing the module containing the function, and the function name. The return value is of type `FunDef` (see [the AST definitions](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/labs01_material/SymbolicTreeModule.scala)).
-  * When comparing Strings by reference, compare the two `StringValue`s directly and not the underlying Strings. The reason is that the JVM may return true when comparing Strings by equality when it is not expected (it has to do with JVM constant pools).
-  * Some functions contained in the `Std` module are built-in in the language, i.e. they are hard-coded in the interpreter because they cannot be implemented in Amy otherwise. An example of a built-in function is `printString`. When you implement the interpreter for function calls, you should first check if the function is built-in, and if so, use the implementation provided in the `builtIns` map in the interpreter.
-  * When a program fails (e.g. due to a call to `error` or a match fail), you should call the dedicated method in the Context: `ctx.reporter.fatal`.
-
-## Implementation skeleton 
-
-If you have followed [Labs Setup](https://gitlab.epfl.ch/lara/cs320/-/blob/main/labs/labs_setup.md) for Lab 01, you should have a working project with a stub implementation, containing the following files:
-
-  * `src/amyc/interpreter/Interpreter.scala` contains a partially implemented interpreter
-  * `src/amyc/Main.scala` contains the `main` method which runs the interpreter on the input files
-  * The `library` directory contains library definitions you can call from your programs.
-  * The `examples` directory contains some example programs on which you can try your implementation. Remember that most of them also use library files from `/library`.
-  * `lib/amy-frontend-1.7.jar` contains the frontend of the compiler as a library, allowing you directly work with type-checked ASTs of input programs.
-
-You will have to complete the interpreter by implementing the missing methods (marked with the placeholder `???`).
-
-
-## Testing
-
-When you are done, use sbt to try some of your programs from Part 1:
-
-```
-  $ sbt
-  > run library/Std.scala examples/Hello.scala
-  Hello world!
-```
-
-There is also testing infrastructure under `/test`. To add your own tests, you have to add your testcases under `/test/resources/interpreter/passing`
-and the expected output under 
-`/test/resources/interpreter/outputs`.
-Then, you have to add the name of the new test in `InterpreterTests`, similarly to the examples given.
-To allow a test to also use the standard library (e.g., `Std.printString`), you can copy `Std.scala` from `library/Std.scala` to `/test/resources/interpreter/passing`.
-
-For example, to add a test that expects only "Hello world" to be printed, you can add "/test/resources/interpreter/passing/Hello.scala" containing `object Hello Std.printString("Hello world") end Hello` and `/test/resources/interpreter/outputs/Hello.txt` containing `Hello world` (with a newline in the end!). You will also have to add a line to `/test/scala/amyc/test/InterpreterTests.scala`:  `@Test def testHello = shouldOutput(List("Std", "Hello"), "Hello")`. This will pass both files `Std.scala` and `Hello.scala` as inputs of the test. When you now run `test` from sbt, you should see the additional test case (called `testHello`).
-
-
-## Deliverables
-You are given **2 weeks** for this assignment.
-
-Deadline: **Friday October 8 at 11 pm**.
-
-Submission: one team member submits a zip file submission-groupNumber.zip to the [moodle submission page](https://moodle.epfl.ch/mod/assign/view.php?id=1169243).
-
-
-## Related documentation 
-
-  * End of Chapter 1 in the Tiger Book presents a similar problem for another mini-language. A comparison of the implementation of ASTs in Java (as shown in the book) and Scala is instructive.

labs/labs_setup.md

-# Labs Setup
-
-This page contains instructions on how to set up your computer to work on assignments.
-
-
-## Step 0: Find a group
-
-All work in this year's edition of CS-320 will be done in groups of two students.
-If you are looking for teammates, please consider using the course's [Moodle](https://moodle.epfl.ch/course/view.php?id=4241) forums.
-One of you should then submit the SCIPER numbers and names of all teammates through [this form](https://docs.google.com/forms/d/18-NX9JvzAVcyUwLruJ-rbkqGD-1qD8EYS_uqAFkC6NQ/edit). Note that you need access the form with epfl email account.
-By the end of the first week you *must* have registered in a group, so you can start working on the lab 1.
-
-
-## Step 1: Version control 
-
-Since you will be working with others throughout the course, we provide all labs via Git repositories.
-Once you have registered as a group, you will be assigned a repository on [EPFL's GitLab](https://gitlab.epfl.ch/).
-For every new lab we are going to push the starter code ("skeleton") on a separate branch of that repository.
-Since all labs starting from the second are cumulative, you should ideally merge your work resulting from the preceding, completed lab into the starter code of the new lab.
-Once the deadline for a lab comes around, we will simply consider your most recent commit on the respective branch as your submission.
-
-
-## Step 2: Java / Scala / SBT 
-
-We will be using Scala 3 to implement our compiler project.
-Please make sure your system is running at least Java 8 and has [SBT](http://www.scala-sbt.org/) (the default build tool for Scala) installed.
-
-
-## Step 3: Working on the labs 
-
-Once you have formed a group and installed SBT, you are ready to start the labs. The workflow for each assignment is roughly as follows:
-  * Check out the branch of the current lab from your repository. Merge with your work from prior labs (when starting work on lab 3, 4 or 5).
-  * Run ''compile'' from inside SBT to make sure your build still succeeds. If you run ''test'' at this point it should fail on some of the new tests provided by us.
-  * Implement the assignment according to the specification. Throughout the semester we will be providing you with details on each specific assignment.
-  * Once you are happy with your solution, make sure one of the team members packages the solution as a zip file with the name **submission-groupNumber.zip**. For instance, if your group number is 3, you would package the lab into a file submission-3.zip. Then go on moodle and send the file in the corresponding assignment.