Assignment 7 Due Tuesday by 23:59 Points 80 Submitting an external tool Assessment Overview Weighting: 80 Points (8% of course grade) Due date: Tuesday 4 Jun, 11:59pm Task description: Develop a Parser to convert high-level programming language into a parse tree. Doing so should help you to: Practice applying grammar rules Understand how complex and nested code structures can be broken down to their component parts. Understand the basics of Recursive Descent Parsing. Please post your questions on Piazza or ask during your workshop. Academic Integrity Checklist Do Discuss/compare high level approaches Discuss/compare program output/errors Regularly submit your work as you progress Be careful Using online resources to find the solutions rather than understanding them yourself won't help you learn. Do NOT Submit code not solely authored by you. Use a public GitHub repository (use a private one instead). Post/share complete VM/Assembly/Machine code in Piazza/Discord or elsewhere on the Internet etc. Give/show your code to others Assignment 7 1/13 Your Task Your task for this practical assignment is to write a parser to convert high-level language programs into a parse tree that can be later converted to VM Code.
- Complete the Parser as described and as outlined below. Submit your work regularly to Gradescope as you progress. Additional resources and help will be available during your workshop sessions.
- Test your code. We're know that things are tight at the end of semester, so we've kept this assignment short (and hopefully simple). Part 1 - Recursive Descent Parser (80 points) We've seen VM Code and how that can be translated to Assembly and Machine code, but these languages are represented as basic sequences of instructions -- how do we handle the nested and varied structures of high-level programming languages? Using your preferred programming language (Python, C++ or Java) implement the CompilerParser 代写 CompilerParser tree high-level programming as described below. This practical assignment follows a similar approach to the Nand2Tetris Compilation Engine. Template files are provided for each of these programming languages.
You will need to complete the methods provided in the CompilerParser class. The provided ParseTree & Token classes should not be modified. Only submit files for 1 programming language. Assignment 7 2/13 Getting Started
- Start by reviewing chapter 10 of the textbook.
- Each of the methods listed below needs to apply the corresponding set of grammar rules to the series of tokens given. For each set of these grammar rules: A new parse tree is created. The tokens are processed 1-by-1. Tokens matching the grammar rule are added to a ParseTree for that rule. If the rules are broken (i.e. the sequence of tokens does not match the rules), a ParseException should be thrown/raised. Otherwise the ParseTree data structure is returned. Some of the sets grammar rules require other sets of grammar rules. For example, the whileStatement rule requires the rules for expression and statements. These rule sets should be applied recursively.
- A ParseTree data structure is returned Tokens Each token has a type and corresponding value. Tokens can have the following types and possible values: Token Type Value keyword symbol integerConstant A decimal integer in the range 0..32767 stringConstant A sequence of characters not including double quote or newline identifier A sequence of letters, digits, and underscore ( ), not starting with a digit. We can read the type of the token with the Token.getType() method, and its value with Token.getValue() You can assume that all tokens have been correctly tokenized (i.e. you will not have to check for and handle bad tokens) Parse Trees Each node in the ParseTree has a type, a value, and a list of children (parse trees nested inside this tree). Assignment 7 3/13 When creating a ParseTree, we set the type and value in the constructor. We can then add parse trees via the ParseTree.addChild(ParseTree) method. If needed, we can read the type of the ParseTree with the ParseTree.getType() method, and its value with ParseTree.getValue() . To review the structure of a ParseTree object, it can be printed; this will output a human readable representation. ParseTrees can have the following types which correspond with a set of grammar rules: Parse Tree Type Grammar Rule class classVarDec subroutine parameterList subroutineBody varDec statements where statement matches the following rule: letStatement ifStatement whileStatement doStatement Assignment 7 4/13 returnStatement expression Note the addition of the skip keyword term expressionList Which match the methods we're implementing. They can also have the same types as listed above for Tokens (and Tokens can be added as children to ParseTrees via typecasting) You may have noticed that some grammar elements shown above and in the Jack WX：codinghelp
