[10] Finishes compiler implementation

master
Nemo 2 years ago
parent 812c76e09a
commit b0aa03980c
  1. 69
      compiler/engine.py
  2. 141
      compiler/grammar.py
  3. 286
      projects/10/ArrayTest/Main.jack.xml
  4. 244
      projects/10/Square/Main.jack.xml
  5. 1211
      projects/10/Square/Square.jack.xml
  6. 643
      projects/10/Square/SquareGame.jack.xml

@ -77,9 +77,16 @@ class Engine:
self.write(line, end="")
self.advance()
for e in grammar:
self.compile(e)
print(lookup_keys)
print("grammar inside matchDict ")
print(grammar)
# Grammar can be none
if grammar:
self.compile(grammar)
# TODO: Improve open and close for dicts
if isinstance(el, Element):
self.close(el)
@ -109,7 +116,7 @@ class Engine:
self.advance()
return True
else:
# print("%s != %s" % (current, expected))
print("%s != %s" % (current, expected))
return False
def open(self, el):
@ -124,29 +131,37 @@ class Engine:
If you set matchOnly = true, the cursor will not move forward
If it is forced to move forward (LL1 grammar for eg,) it will raise an error instead
"""
def compile(self, thing, matchOnly = False):
if isinstance(thing, Element):
ret = self.compile(thing.grammar[0], True)
if (matchOnly == False and ret) or thing.empty:
self.open(thing)
for e in thing.grammar:
def compile(self, grammar, matchOnly = False):
if callable(grammar):
ret = self.compile(grammar(), matchOnly)
elif isinstance(grammar, Element):
ret = self.compile(grammar.grammar, True)
if grammar.name == 'term':
print(ret)
print(self.atom())
if (matchOnly == False and ret) or grammar.empty:
self.open(grammar)
# Avoid useless compilation
if ret:
ret = self.compile(grammar.grammar)
self.close(grammar)
elif isinstance(grammar, Sequence):
if matchOnly:
ret = self.compile(grammar[0], True)
else:
for e in grammar:
ret = self.compile(e)
self.close(thing)
return ret
elif callable(thing):
grammar = thing()
return self.compile(grammar, matchOnly)
elif isinstance(grammar, list):
ret = self.ZeroOrMany(grammar, matchOnly)
elif isinstance(grammar,dict):
ret = self.MatchDict(grammar, matchOnly)
elif isinstance(grammar,tuple):
ret = self.ZeroOrOne(grammar, matchOnly)
elif isinstance(grammar,Atom):
ret = self.MatchAtom(grammar, matchOnly)
else:
grammar = thing
grammarType = type(grammar)
if grammarType == list:
return self.ZeroOrMany(grammar, matchOnly)
elif grammarType == dict:
return self.MatchDict(grammar, matchOnly)
elif grammarType == tuple:
return self.ZeroOrOne(grammar, matchOnly)
elif grammarType == Atom:
return self.MatchAtom(grammar, matchOnly)
else:
raise Exception("Should not have reached here")
raise Exception("Invalid Grammar")
return ret

@ -20,73 +20,109 @@ This is basically an attempt to translate Figure 10.5 from the book into
a Python structure.
"""
class Sequence(list):
def first(self):
return self[0]
class Element:
# Usually I avoid inverted boolean variable names, but this is much cleaner
def __init__(self, name, grammar):
assert(type(grammar)==list)
# Since Any derives from list, this ought to work
assert(isinstance(grammar, list) or isinstance(grammar, dict))
self.name = name
self.grammar = grammar
self.empty = False
def first(self):
if isinstance(self.grammar, list):
return self.grammar[0]
elif isinstance(self.grammar, dict):
return list(self.grammar.keys())[0]
def __repr__(self):
return self.name
CLASSVARDEC = Element('classVarDec', [
CLASSVARDEC = Element('classVarDec', Sequence([
# static|field type (, name)* ;
Atom.STATIC | Atom.FIELD,
Atom.INT | Atom.CHAR | Atom.BOOLEAN | Atom.IDENTIFIER,
Atom.IDENTIFIER,
# Zero or one of these
[Atom.COMMA, Atom.IDENTIFIER],
Atom.SEMICOLON
])
]))
VARDEC = Element('varDec', [Atom.VAR, Atom.INT | Atom.CHAR | Atom.BOOLEAN | Atom.IDENTIFIER, Atom.IDENTIFIER,
VARDEC = Element('varDec', Sequence([
Atom.VAR, Atom.INT | Atom.CHAR | Atom.BOOLEAN | Atom.IDENTIFIER, Atom.IDENTIFIER,
# Zero or one of these
[Atom.COMMA, Atom.IDENTIFIER],
Atom.SEMICOLON
])
]))
# Since this is not a non-terminal, we can just write it as a constant
# Since these are not a non-terminal, we can just write it as a constant
OP = Atom.PLUS | Atom.MINUS | Atom.MUL | Atom.DIV | Atom.AND | Atom.OR | Atom.GT | Atom.LT | Atom.EQ
UNARY_OP = Atom.NOT | Atom.MINUS
CONSTANT = Atom.TRUE | Atom.FALSE|Atom.NULL|Atom.THIS
CONSTANT = Atom.TRUE | Atom.FALSE | Atom.NULL | Atom.THIS
""" Pseudo-element to help define subroutine declarations """
RETURN_TYPES= Atom.INT | Atom.CHAR|Atom.BOOLEAN|Atom.IDENTIFIER|Atom.VOID
# TODO: This is missing the following:
# var [expression]
# subRoutineCall
# (expressions in parenthes)
# unaryOP TERM
TERM = Element('term', [
Atom.INTEGERCONSTANT | Atom.STRINGCONSTANT | Atom.TRUE | Atom.FALSE | Atom.NULL| Atom.THIS | Atom.IDENTIFIER
])
EXPRESSION = Element('expression', [TERM, [OP, TERM]])
EXPRESSIONLIST = Element('expressionList', [(EXPRESSION, [Atom.COMMA, EXPRESSION])])
DO_STATEMENT = Element('doStatement', [{
(Atom.IDENTIFIER, Atom.PAREN_OPEN): [
EXPRESSIONLIST,
Atom.PAREN_CLOSE,
],
(Atom.IDENTIFIER, Atom.DOT): [
Atom.IDENTIFIER,
Atom.PAREN_OPEN,
EXPRESSIONLIST,
Atom.PAREN_CLOSE
]
},Atom.SEMICOLON])
LET_STATEMENT = Element('letStatement', [
RETURN_TYPES= Atom.INT | Atom.CHAR | Atom.BOOLEAN | Atom.IDENTIFIER | Atom.VOID
# This is a flattened version of the Term structure
TERM = Element('term', {
(Atom.INTEGERCONSTANT,): None,
(Atom.STRINGCONSTANT,): None,
(Atom.TRUE,): None,
(Atom.FALSE,): None,
(Atom.NULL,): None,
(Atom.THIS,): None,
# unaryOp TERM
(Atom.NOT,): Sequence([lambda: TERM]),
(Atom.MINUS,): Sequence([lambda: TERM]),
# (expression)
(Atom.PAREN_OPEN,): Sequence([lambda: EXPRESSION, Atom.PAREN_CLOSE]),
(Atom.IDENTIFIER,): {
# array lookup
(Atom.SQUARE_OPEN,): Sequence([lambda: EXPRESSION, Atom.SQUARE_CLOSE]),
# Subroutine call, but with class name
(Atom.DOT,): Sequence([
Atom.IDENTIFIER,
Atom.PAREN_OPEN,
lambda: EXPRESSIONLIST,
Atom.PAREN_CLOSE
]),
# Subroutine call, but to same class
(Atom.PAREN_OPEN,): Sequence([
lambda: EXPRESSIONLIST,
Atom.PAREN_CLOSE
])
}
})
EXPRESSION = Element('expression', Sequence([TERM, [OP, TERM]]))
EXPRESSIONLIST = Element('expressionList', Sequence([
(EXPRESSION, [Atom.COMMA, EXPRESSION])
]))
SUBROUTINE_CALL = [
(Atom.IDENTIFIER, Atom.DOT),
Atom.IDENTIFIER,
Atom.PAREN_OPEN,
EXPRESSIONLIST,
Atom.PAREN_CLOSE
]
DO_STATEMENT = Element('doStatement', Sequence([SUBROUTINE_CALL,Atom.SEMICOLON]))
LET_STATEMENT = Element('letStatement', Sequence([
Atom.IDENTIFIER,
(Atom.SQUARE_OPEN, EXPRESSION, Atom.SQUARE_CLOSE),
Atom.EQ,
EXPRESSION,
Atom.SEMICOLON
])
]))
IF_STATEMENT = Element('ifStatement', [
IF_STATEMENT = Element('ifStatement', Sequence([
Atom.PAREN_OPEN,
EXPRESSION,
Atom.PAREN_CLOSE,
@ -95,18 +131,20 @@ IF_STATEMENT = Element('ifStatement', [
Atom.BRACE_CLOSE,
# This is the tricky one
( Atom.ELSE, Atom.BRACE_OPEN, lambda:STATEMENTS, Atom.BRACE_CLOSE)
])
]))
WHILE_STATEMENT = Element('whileStatement', [
WHILE_STATEMENT = Element('whileStatement', Sequence([
Atom.PAREN_OPEN,
EXPRESSION,
Atom.PAREN_CLOSE,
Atom.BRACE_OPEN,
lambda: STATEMENTS,
Atom.BRACE_CLOSE,
])
]))
RETURN_STATEMENT = Element('returnStatement', [(EXPRESSION), Atom.SEMICOLON])
RETURN_STATEMENT = Element('returnStatement', Sequence([
(EXPRESSION), Atom.SEMICOLON
]))
# Just a constant, since this isn't a non-terminal
STATEMENT = {
@ -117,31 +155,32 @@ STATEMENT = {
(Atom.RETURN,): RETURN_STATEMENT
}
STATEMENTS = Element('statements', [[STATEMENT]])
STATEMENTS = Element('statements', Sequence([[STATEMENT]]))
SUBROUTINE_BODY = Element('subroutineBody', [
SUBROUTINE_BODY = Element('subroutineBody', Sequence([
# One or more variable declarations
# `var type varName (, varName)* ;`
Atom.BRACE_OPEN,
[VARDEC],
STATEMENTS,
Atom.BRACE_CLOSE
])
]))
# Parameter List =
# (
# (type varName) (, type varName)*
# )?
# we use tuples for zero OR one of a sequence
PARAMETER_LIST = Element('parameterList', [(
PARAMETER_LIST = Element('parameterList', Sequence([(
Atom.INT | Atom.CHAR | Atom.BOOLEAN | Atom.IDENTIFIER,
Atom.IDENTIFIER,
# Zero or one of the following:
[Atom.COMMA, Atom.INT | Atom.CHAR|Atom.BOOLEAN|Atom.IDENTIFIER, Atom.IDENTIFIER]
)])
)]))
EXPRESSIONLIST.empty = PARAMETER_LIST.empty = True
SUBROUTINEDEC = Element('subroutineDec', [
SUBROUTINEDEC = Element('subroutineDec', Sequence([
# (constructor | function | method) (void | type) subRoutineName '(' parameterList ')'
# subroutineBody
Atom.CONSTRUCTOR | Atom.FUNCTION | Atom.METHOD,
@ -151,13 +190,13 @@ SUBROUTINEDEC = Element('subroutineDec', [
PARAMETER_LIST,
Atom.PAREN_CLOSE,
SUBROUTINE_BODY,
])
]))
CLASS = Element('class', [
CLASS = Element('class', Sequence([
Atom.CLASS,
Atom.IDENTIFIER,
Atom.BRACE_OPEN,
[CLASSVARDEC],
[SUBROUTINEDEC],
Atom.BRACE_CLOSE
])
]))

@ -0,0 +1,286 @@
<class>
<keyword> class </keyword>
<identifier> Main </identifier>
<symbol> { </symbol>
<subroutineDec>
<keyword> function </keyword>
<keyword> void </keyword>
<identifier> main </identifier>
<symbol> ( </symbol>
<parameterList>
</parameterList>
<symbol> ) </symbol>
<subroutineBody>
<symbol> { </symbol>
<varDec>
<keyword> var </keyword>
<identifier> Array </identifier>
<identifier> a </identifier>
<symbol> ; </symbol>
</varDec>
<varDec>
<keyword> var </keyword>
<keyword> int </keyword>
<identifier> length </identifier>
<symbol> ; </symbol>
</varDec>
<varDec>
<keyword> var </keyword>
<keyword> int </keyword>
<identifier> i </identifier>
<symbol> , </symbol>
<identifier> sum </identifier>
<symbol> ; </symbol>
</varDec>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> length </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> Keyboard </identifier>
<symbol> . </symbol>
<identifier> readInt </identifier>
<symbol> ( </symbol>
<expressionList>
<expression>
<term>
<stringconstant> HOW MANY NUMBERS? </stringconstant>
</term>
</expression>
</expressionList>
<symbol> ) </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> a </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> Array </identifier>
<symbol> . </symbol>
<identifier> new </identifier>
<symbol> ( </symbol>
<expressionList>
<expression>
<term>
<identifier> length </identifier>
</term>
</expression>
</expressionList>
<symbol> ) </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> i </identifier>
<symbol> = </symbol>
<expression>
<term>
<integerconstant> 0 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<whileStatement>
<keyword> while </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> i </identifier>
</term>
<symbol> &lt; </symbol>
<term>
<identifier> length </identifier>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> a </identifier>
<symbol> [ </symbol>
<expression>
<term>
<identifier> i </identifier>
</term>
</expression>
<symbol> ] </symbol>
<symbol> = </symbol>
<expression>
<term>
<identifier> Keyboard </identifier>
<symbol> . </symbol>
<identifier> readInt </identifier>
<symbol> ( </symbol>
<expressionList>
<expression>
<term>
<stringconstant> ENTER THE NEXT NUMBER: </stringconstant>
</term>
</expression>
</expressionList>
<symbol> ) </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> i </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> i </identifier>
</term>
<symbol> + </symbol>
<term>
<integerconstant> 1 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
</statements>
<symbol> } </symbol>
</whileStatement>
<letStatement>
<keyword> let </keyword>
<identifier> i </identifier>
<symbol> = </symbol>
<expression>
<term>
<integerconstant> 0 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> sum </identifier>
<symbol> = </symbol>
<expression>
<term>
<integerconstant> 0 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<whileStatement>
<keyword> while </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> i </identifier>
</term>
<symbol> &lt; </symbol>
<term>
<identifier> length </identifier>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> sum </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> sum </identifier>
</term>
<symbol> + </symbol>
<term>
<identifier> a </identifier>
<symbol> [ </symbol>
<expression>
<term>
<identifier> i </identifier>
</term>
</expression>
<symbol> ] </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> i </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> i </identifier>
</term>
<symbol> + </symbol>
<term>
<integerconstant> 1 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
</statements>
<symbol> } </symbol>
</whileStatement>
<doStatement>
<keyword> do </keyword>
<identifier> Output </identifier>
<symbol> . </symbol>
<identifier> printString </identifier>
<symbol> ( </symbol>
<expressionList>
<expression>
<term>
<stringconstant> THE AVERAGE IS: </stringconstant>
</term>
</expression>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
<doStatement>
<keyword> do </keyword>
<identifier> Output </identifier>
<symbol> . </symbol>
<identifier> printInt </identifier>
<symbol> ( </symbol>
<expressionList>
<expression>
<term>
<identifier> sum </identifier>
</term>
<symbol> / </symbol>
<term>
<identifier> length </identifier>
</term>
</expression>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
<doStatement>
<keyword> do </keyword>
<identifier> Output </identifier>
<symbol> . </symbol>
<identifier> println </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
<returnStatement>
<keyword> return </keyword>
<symbol> ; </symbol>
</returnStatement>
</statements>
<symbol> } </symbol>
</subroutineBody>
</subroutineDec>
<symbol> } </symbol>
</class>

@ -0,0 +1,244 @@
<class>
<keyword> class </keyword>
<identifier> Main </identifier>
<symbol> { </symbol>
<classVarDec>
<keyword> static </keyword>
<keyword> boolean </keyword>
<identifier> test </identifier>
<symbol> ; </symbol>
</classVarDec>
<subroutineDec>
<keyword> function </keyword>
<keyword> void </keyword>
<identifier> main </identifier>
<symbol> ( </symbol>
<parameterList>
</parameterList>
<symbol> ) </symbol>
<subroutineBody>
<symbol> { </symbol>
<varDec>
<keyword> var </keyword>
<identifier> SquareGame </identifier>
<identifier> game </identifier>
<symbol> ; </symbol>
</varDec>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> game </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> SquareGame </identifier>
<symbol> . </symbol>
<identifier> new </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<doStatement>
<keyword> do </keyword>
<identifier> game </identifier>
<symbol> . </symbol>
<identifier> run </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
<doStatement>
<keyword> do </keyword>
<identifier> game </identifier>
<symbol> . </symbol>
<identifier> dispose </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
<returnStatement>
<keyword> return </keyword>
<symbol> ; </symbol>
</returnStatement>
</statements>
<symbol> } </symbol>
</subroutineBody>
</subroutineDec>
<subroutineDec>
<keyword> function </keyword>
<keyword> void </keyword>
<identifier> test </identifier>
<symbol> ( </symbol>
<parameterList>
</parameterList>
<symbol> ) </symbol>
<subroutineBody>
<symbol> { </symbol>
<varDec>
<keyword> var </keyword>
<keyword> int </keyword>
<identifier> i </identifier>
<symbol> , </symbol>
<identifier> j </identifier>
<symbol> ; </symbol>
</varDec>
<varDec>
<keyword> var </keyword>
<identifier> String </identifier>
<identifier> s </identifier>
<symbol> ; </symbol>
</varDec>
<varDec>
<keyword> var </keyword>
<identifier> Array </identifier>
<identifier> a </identifier>
<symbol> ; </symbol>
</varDec>
<statements>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<keyword> false </keyword>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> s </identifier>
<symbol> = </symbol>
<expression>
<term>
<stringconstant> string constant </stringconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> s </identifier>
<symbol> = </symbol>
<expression>
<term>
<keyword> null </keyword>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> a </identifier>
<symbol> [ </symbol>
<expression>
<term>
<integerconstant> 1 </integerconstant>
</term>
</expression>
<symbol> ] </symbol>
<symbol> = </symbol>
<expression>
<term>
<identifier> a </identifier>
<symbol> [ </symbol>
<expression>
<term>
<integerconstant> 2 </integerconstant>
</term>
</expression>
<symbol> ] </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
</statements>
<symbol> } </symbol>
<keyword> else </keyword>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> i </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> i </identifier>
</term>
<symbol> * </symbol>
<term>
<symbol> ( </symbol>
<expression>
<term>
<symbol> - </symbol>
<term>
<identifier> j </identifier>
</term>
</term>
</expression>
<symbol> ) </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> j </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> j </identifier>
</term>
<symbol> / </symbol>
<term>
<symbol> ( </symbol>
<expression>
<term>
<symbol> - </symbol>
<term>
<integerconstant> 2 </integerconstant>
</term>
</term>
</expression>
<symbol> ) </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> i </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> i </identifier>
</term>
<symbol> | </symbol>
<term>
<identifier> j </identifier>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<returnStatement>
<keyword> return </keyword>
<symbol> ; </symbol>
</returnStatement>
</statements>
<symbol> } </symbol>
</subroutineBody>
</subroutineDec>
<symbol> } </symbol>
</class>

File diff suppressed because it is too large Load Diff

@ -0,0 +1,643 @@
<class>
<keyword> class </keyword>
<identifier> SquareGame </identifier>
<symbol> { </symbol>
<classVarDec>
<keyword> field </keyword>
<identifier> Square </identifier>
<identifier> square </identifier>
<symbol> ; </symbol>
</classVarDec>
<classVarDec>
<keyword> field </keyword>
<keyword> int </keyword>
<identifier> direction </identifier>
<symbol> ; </symbol>
</classVarDec>
<subroutineDec>
<keyword> constructor </keyword>
<identifier> SquareGame </identifier>
<identifier> new </identifier>
<symbol> ( </symbol>
<parameterList>
</parameterList>
<symbol> ) </symbol>
<subroutineBody>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> square </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> Square </identifier>
<symbol> . </symbol>
<identifier> new </identifier>
<symbol> ( </symbol>
<expressionList>
<expression>
<term>
<integerconstant> 0 </integerconstant>
</term>
</expression>
<symbol> , </symbol>
<expression>
<term>
<integerconstant> 0 </integerconstant>
</term>
</expression>
<symbol> , </symbol>
<expression>
<term>
<integerconstant> 30 </integerconstant>
</term>
</expression>
</expressionList>
<symbol> ) </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<letStatement>
<keyword> let </keyword>
<identifier> direction </identifier>
<symbol> = </symbol>
<expression>
<term>
<integerconstant> 0 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<returnStatement>
<keyword> return </keyword>
<expression>
<term>
<keyword> this </keyword>
</term>
</expression>
<symbol> ; </symbol>
</returnStatement>
</statements>
<symbol> } </symbol>
</subroutineBody>
</subroutineDec>
<subroutineDec>
<keyword> method </keyword>
<keyword> void </keyword>
<identifier> dispose </identifier>
<symbol> ( </symbol>
<parameterList>
</parameterList>
<symbol> ) </symbol>
<subroutineBody>
<symbol> { </symbol>
<statements>
<doStatement>
<keyword> do </keyword>
<identifier> square </identifier>
<symbol> . </symbol>
<identifier> dispose </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
<doStatement>
<keyword> do </keyword>
<identifier> Memory </identifier>
<symbol> . </symbol>
<identifier> deAlloc </identifier>
<symbol> ( </symbol>
<expressionList>
<expression>
<term>
<keyword> this </keyword>
</term>
</expression>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
<returnStatement>
<keyword> return </keyword>
<symbol> ; </symbol>
</returnStatement>
</statements>
<symbol> } </symbol>
</subroutineBody>
</subroutineDec>
<subroutineDec>
<keyword> method </keyword>
<keyword> void </keyword>
<identifier> moveSquare </identifier>
<symbol> ( </symbol>
<parameterList>
</parameterList>
<symbol> ) </symbol>
<subroutineBody>
<symbol> { </symbol>
<statements>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> direction </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 1 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<doStatement>
<keyword> do </keyword>
<identifier> square </identifier>
<symbol> . </symbol>
<identifier> moveUp </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> direction </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 2 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<doStatement>
<keyword> do </keyword>
<identifier> square </identifier>
<symbol> . </symbol>
<identifier> moveDown </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> direction </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 3 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<doStatement>
<keyword> do </keyword>
<identifier> square </identifier>
<symbol> . </symbol>
<identifier> moveLeft </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> direction </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 4 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<doStatement>
<keyword> do </keyword>
<identifier> square </identifier>
<symbol> . </symbol>
<identifier> moveRight </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<doStatement>
<keyword> do </keyword>
<identifier> Sys </identifier>
<symbol> . </symbol>
<identifier> wait </identifier>
<symbol> ( </symbol>
<expressionList>
<expression>
<term>
<integerconstant> 5 </integerconstant>
</term>
</expression>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
<returnStatement>
<keyword> return </keyword>
<symbol> ; </symbol>
</returnStatement>
</statements>
<symbol> } </symbol>
</subroutineBody>
</subroutineDec>
<subroutineDec>
<keyword> method </keyword>
<keyword> void </keyword>
<identifier> run </identifier>
<symbol> ( </symbol>
<parameterList>
</parameterList>
<symbol> ) </symbol>
<subroutineBody>
<symbol> { </symbol>
<varDec>
<keyword> var </keyword>
<keyword> char </keyword>
<identifier> key </identifier>
<symbol> ; </symbol>
</varDec>
<varDec>
<keyword> var </keyword>
<keyword> boolean </keyword>
<identifier> exit </identifier>
<symbol> ; </symbol>
</varDec>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> exit </identifier>
<symbol> = </symbol>
<expression>
<term>
<keyword> false </keyword>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<whileStatement>
<keyword> while </keyword>
<symbol> ( </symbol>
<expression>
<term>
<symbol> ~ </symbol>
<term>
<identifier> exit </identifier>
</term>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<whileStatement>
<keyword> while </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> key </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 0 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> key </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> Keyboard </identifier>
<symbol> . </symbol>
<identifier> keyPressed </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<doStatement>
<keyword> do </keyword>
<identifier> moveSquare </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
</statements>
<symbol> } </symbol>
</whileStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> key </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 81 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> exit </identifier>
<symbol> = </symbol>
<expression>
<term>
<keyword> true </keyword>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> key </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 90 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<doStatement>
<keyword> do </keyword>
<identifier> square </identifier>
<symbol> . </symbol>
<identifier> decSize </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> key </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 88 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<doStatement>
<keyword> do </keyword>
<identifier> square </identifier>
<symbol> . </symbol>
<identifier> incSize </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ; </symbol>
</doStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> key </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 131 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> direction </identifier>
<symbol> = </symbol>
<expression>
<term>
<integerconstant> 1 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> key </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 133 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> direction </identifier>
<symbol> = </symbol>
<expression>
<term>
<integerconstant> 2 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> key </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 130 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> direction </identifier>
<symbol> = </symbol>
<expression>
<term>
<integerconstant> 3 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<ifStatement>
<keyword> if </keyword>
<symbol> ( </symbol>
<expression>
<term>
<identifier> key </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 132 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> direction </identifier>
<symbol> = </symbol>
<expression>
<term>
<integerconstant> 4 </integerconstant>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
</statements>
<symbol> } </symbol>
</ifStatement>
<whileStatement>
<keyword> while </keyword>
<symbol> ( </symbol>
<expression>
<term>
<symbol> ~ </symbol>
<term>
<symbol> ( </symbol>
<expression>
<term>
<identifier> key </identifier>
</term>
<symbol> = </symbol>
<term>
<integerconstant> 0 </integerconstant>
</term>
</expression>
<symbol> ) </symbol>
</term>
</term>
</expression>
<symbol> ) </symbol>
<symbol> { </symbol>
<statements>
<letStatement>
<keyword> let </keyword>
<identifier> key </identifier>
<symbol> = </symbol>
<expression>
<term>
<identifier> Keyboard </identifier>
<symbol> . </symbol>
<identifier> keyPressed </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
</term>
</expression>
<symbol> ; </symbol>
</letStatement>
<doStatement>
<keyword> do </keyword>
<identifier> moveSquare </identifier>
<symbol> ( </symbol>
<expressionList>
</expressionList>
<symbol> ) </symbol>
<symbol> ;