program代写、代做Python, C++/Java编程

日期：2023-11-12 10:19

Practical Assignment 7

? Assessment Overview

Weighting: 80 Points (8% of course grade)

Due date: Friday 28 Sunday 30 Oct Thursday 3 Nov 11:59 pm (SWOT Week)

Gradescope open now

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

? 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.

1. 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.

2. 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 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.

Download the Python version HERE

(https://myuni.adelaide.edu.au/courses/72399/files/11771254?wrap=1)

(https://myuni.adelaide.edu.au/courses/72399/files/11771254/download?

download_frd=1) .

Download the Java version HERE

(https://myuni.adelaide.edu.au/courses/72399/files/11771151?wrap=1)

(https://myuni.adelaide.edu.au/courses/72399/files/11771151/download?

download_frd=1) .

Download the C++ version HERE

(https://myuni.adelaide.edu.au/courses/72399/files/11772199?wrap=1)

(https://myuni.adelaide.edu.au/courses/72399/files/11772199/download?

download_frd=1) .

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.

Getting Started

1. Start by reviewing chapter 10 of the textbook.

2. 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.

3. 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()

Parse Trees

Each node in the ParseTree has a type, a value, and a list of children (parse trees nested

inside this tree).

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

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 Grammar

are missing from this list. These rules are listed below. They should be used as part of the

rules above, but are not themselves ParseTree types:

Grammar

Element

Grammar Rule

className

varName

subroutineName

type

op

unaryOp

keywordConstant

subroutineCall

Suggested Approach

A suggested approach is outlined in section 10.1.4 of the Text book.

This involves writing a process(token) method which:

Checks if the next token in the list of tokens matches an expected token

If the token matches, add it to the ParseTree

If the token does not match, throw/raise a ParseError

Advances to the next token (if needed)

This can be done by removing/popping the token from the list

Task 1.1 - Program Structure (40 points)

Complete the program structure related methods:

compileProgram

Jack Code Tokens

Returned ParseTree

Structure

class Main {

}

keyword class

identifier Main

symbol {

symbol }

class

keyword class

identifier Main

symbol {

symbol }

static int a ;

keyword static

keyword int

identifier a

symbol ;

ParseError (the program doesn't

begin with a class)

compileClass

Example Jack Code Tokens

Returned ParseTree

Structure

class Main {

static int a ;

}

keyword class

identifier Main

symbol {

keyword static

keyword int

identifier a

symbol ;

symbol }

class

keyword class

identifier Main

symbol {

classVarDec

...

see

classVarDec

below

symbol }

compileClassVarDec

Example Jack Code Tokens

Returned ParseTree

Structure

static int a ;

keyword static

keyword int

identifier a

symbol ;

classVarDec

keyword static

keyword int

identifier a

symbol ;

compileSubroutine

Example Jack Code Tokens

Returned ParseTree

Structure

function void myFunc ( i

nt a ) {

  var int a ;

let a = 1 ;

}

keyword function

keyword void

identifier myFunc

symbol (

keyword int

identifier a

symbol )

symbol {

keyword var

keyword int

identifier a

symbol ;

keyword let

identifier a

symbol =

integerConstant 1

symbol ;

}

subroutine

keyword function

keyword void

identifier myFunc

symbol (

parameterList

...

(see

parameterList

below)

symbol )

subroutineBody

...

see

subroutineBody

below

compileParameterList

Example Jack Code Tokens

Returned ParseTree

Structure

int a, char b

keyword int

identifier a

symbol ,

keyword char

identifier b

parameterList

keyword int

identifier a

symbol ,

keyword char

identifier b

compileSubroutineBody

Example Jack Code Tokens

Returned ParseTree

Structure

{

  var int a ;

  let a = 1 ;

}

symbol {

keyword var

keyword int

identifier a

symbol ;

keyword let

identifier a

symbol =

integerConstant 1

symbol ;

}

subroutineBody

symbol {

varDec

...

(see varDec

below)

statements

...

(see

statements

below)

symbol }

compileVarDec

Example Jack Code Tokens

Returned ParseTree

Structure

var int a ;

keyword var

keyword int

identifier a

symbol ;

varDec

keyword var

keyword int

identifier a

symbol ;

Task 1.2 - Statements (40 points)

Complete the statement related methods:

compileStatements

Example Jack Code Tokens

Returned ParseTree

Structure

let a = skip ;

do skip ;

return ;

keyword let

identifier a

symbol =

keyword skip

symbol ;

keyword do

keyword skip

symbol ;

keyword return

symbol ;

statements

letStatement

...

(see

letStatement

below)

doStatement

...

(see

doStatement

below)

returnStatement

...

(see

doStatement

below)

compileLet

Example Jack Code Tokens

Returned ParseTree

Structure

let a = skip ;

keyword let

identifier a

symbol =

keyword skip

symbol ;

letStatement

keyword let

identifier a

symbol =

expression

...

see

expression

below

symbol ;

compileIf

Example Jack Code Tokens

Returned ParseTree

Structure

if ( skip )

compileReturn

Example Jack Code

Tokens

Returned ParseTree

Structure

return skip ;

keyword return

keyword skip

symbol ;

returnStatement

keyword return

expression

...

see

expression

below

symbol ;

For some of the above methods, you will also need to partially implement the

compileExpression method below.

At this stage, implement the compileExpression to match the grammar rule .

Task 1.3 - Expressions (Optional - up to 20 BONUS points)

Complete the expression related methods:

This section is optional and is worth Bonus Points

compileExpression

Example Jack Code Tokens

Returned ParseTree

Structure

skip keyword skip

expression

keyword skip

1 + ( a - b )

integerConstant 1

symbol +

symbol (

identifier a

symbol -

identifier b

symbol )

expression

term

...

see term

below

symbol +

term

...

see term

below

compileTerm

Example Jack Code Tokens

Returned ParseTree

Structure

1

integerConstant 1

term

integerConstant 1

( a - b ) symbol (

identifier a

symbol -

identifier b

symbol )

term

symbol (

expression

term

identifier

a

symbol -

term

? You're done!

Submit your work to Gradescope using the button below.

You may submit via file upload or GitHub.

If using GitHub, ensure your repository is private.

Your files should either be:

In the root of your submission (i.e. no subdirectory)

~ or ~

In a directory named prac7

Be sure to submit all files with each submission.

? Additional Resources

The following resources may help you complete this assignment:

identifier

b

symbol )

compileExpressionList

Example Jack Code Tokens

Returned ParseTree

Structure

1 , a - b

integerConstant 1

symbol ,

identifier a

symbol -

identifier b

expressionList

expression

...

see

expression

above

symbol ,

expression

...

see

expression

above

Examples

See above

This tool needs to be loaded in a new browser window

Chapter 10 of the Text Book

(https://myuni.adelaide.edu.au/courses/72399/external_tools/1284) for Compiler

Implementation

Section 10.1.4 includes basics of a suggested approach.

Week 11 & 12 Workshops

Guide to Testing and Writing Test Cases

(https://myuni.adelaide.edu.au/courses/72399/pages/guide-to-testing-and-writing-test-cases)

Figure 10.5 on page 201 of the Text Book

(https://myuni.adelaide.edu.au/courses/72399/external_tools/1284) for specification of the

Jack Grammar.

Further resources will be added over the coming days.

Gradescope Link Temporarily Broken - Log In directly using "School Credentials"

https://www.gradescope.com/ (https://www.gradescope.com/)

See Pinned post in Piazza if having issues with the above.

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