Work from yesterday on the CompilationEngine

- Restructured the grammar into a separate python
  module today
- Doesn't cover array expressions and subroutine calls
  inside expressions
master
Nemo 2 years ago
parent c71dd21128
commit d209fabc9a
  1. 123
      compiler/compilation.py
  2. 120
      compiler/grammar.py

@ -0,0 +1,123 @@
from grammar import GRAMMAR
class CompilationEngine:
def xml_file(self, input_file):
return input_file + ".xml"
""" Calling keyword does an implicit assert """
def k(self):
assert(self.jt.tokenType() == Token.KEYWORD)
return CompilationEngine.KEYWORD_MAP[self.jt.current_token()]
def v(self):
assert(self.type() == Token.SYMBOL or self.type() == Token.IDENTIFIER)
return self.jt.current_token()
""" Opens one of the heirarchial tags """
def open(self, tag):
self.file.write((self.i * " ") + "<%s>" % tag)
self.i+=2
""" Closes a tag """
def close(self, tag):
self.file.write((self.i * " ") + "<%s>" % tag)
self.i-=2
""" Advances the Tokenizer and prints a debug statement"""
def advance(self):
old = self.jt.current_token()
self.jt.advance()
print("Advanced from {old} to {t} {new}".format(t=self.type(),old=old, new=self.jt.current_token()))
def type(self):
return self.jt.tokenType()
def s(self):
return CompilationEngine.SYMBOL_MAP[self.jt.symbol()]
def CompileClass(self):
self.open("class")
self.do_the_thing(Keyword.CLASS, Token.IDENTIFIER, Symbol.BRACE_OPEN)
while(not (self.type() == Token.SYMBOL and self.v() == '}' )):
if (self.k() in [Keyword.STATIC, Keyword.FIELD]):
self.CompileClassVarDec()
elif(self.k() in [Keyword.CONSTRUCTOR, Keyword.FUNCTION, Keyword.METHOD]):
self.CompuleSubroutine()
else:
raise RuntimeError("Invalid Token")
assert(self.type() == Token.SYMBOL and self.v() == '}')
self.close("class")
def we_need_a_type(self):
if (self.type() == Token.Keyword):
self.do_the_thing(Keyword.INT | Keyword.CHAR | Keyword.BOOLEAN)
else:
self.do_the_thing(Token.IDENTIFIER)
def CompileClassVarDec(self):
self.open('classVarDec')
self.do_the_thing(Keyword.STATIC | Keyword.FIELD)
self.we_need_a_type()
self.do_the_thing(Token.IDENTIFIER, [SYMBOL.PARAN_OPEN, Token.IDENTIFIER])
self.close('classVarDec')
self.advance()
""" Writes a single line(with \n) on the XML, taking into account the indentation """
def write(self, klass, subklass = None):
print(self.type())
print(klass)
assert(klass == self.type())
if (klass == Token.SYMBOL):
assert(subklass == self.s())
elif(klass == Token.KEYWORD):
assert(subklass & self.k())
elif(subklass == Token.INTEGERCONSTANT):
self.jt.intVal()
self.file.write((self.i * " ") + self.jt.xml_row())
def matches(self, T):
return (isinstance(T, Symbol) and T == self.s()) or (isinstance(T, Keyword) and T & self.k()) or T==Token.INTEGERCONSTANT or T==Token.STRINGCONSTANT
def do_the_thing(self,*args):
for T in args:
# We use a list for *, which is zero or more times
if isinstance(T, list):
# LL(0) for now
if
if isinstance(T, Symbol):
self.write(Token.SYMBOL, T)
elif isinstance(T, Keyword):
self.write(Token.KEYWORD, T)
else:
assert(self.type() in [Token.IDENTIFIER, Token.INTEGERCONSTANT, Token.STRINGCONSTANT])
self.write(T)
self.advance()
def CompuleSubroutine(self):
self.open('subroutineDec')
self.write()
pass
def CompuleParameterList(self):
pass
def CompileVarDec(self):
pass
def CompileStatements(self):
pass
def CompileDo(self):
pass
def CompileLet(self):
pass
def CompileWhile(self):
pass
def CompileReturn(self):
pass
def CompileIf(self):
pass
def CompileTerm(self):
pass
def __init__(self, input_file):
self.i = 0
self.jt = JackTokenizer(input_file, False)
self.file = open(self.xml_file(input_file), 'w')

@ -0,0 +1,120 @@
from keywords import Keyword
"""
The grammar is defined by the following constructs:
The top level object is called GRAMMAR, which is the grammar for a class. It is a list object.
Inside this list, each element can be any of the following:
- a token (denoted by a Keyword enum)
- a bitwise mask of the Keyword enum to denote multiple possibilities
- Another list, to denote zero-or-more of a inner-sequence
- A tuple, to denote zero-or-one of a inner-sequence
This is basically an attempt to translate Figure 10.5 from the book into
a Python structure.
"""
TYPE = Keyword.INT | Keyword.CHAR | Keyword.BOOLEAN | Keyword.IDENTIFIER
UNARY_OP = Keyword.NOT | Keyword.MINUS
TERM = Keyword.INTEGERCONSTANT | Keyword.STRINGCONSTANT | Keyword.TRUE | Keyword.FALSE | Keyword.IDENTIFIER
OP = Keyword.PLUS | Keyword.MINUS | Keyword.MUL | Keyword.DIV | Keyword.AND | Keyword.OR | Keyword.GT | Keyword.LT | Keyword.EQ
EXPRESSION = [TERM, [OP, TERM]]
EXPRESSIONLIST = (EXPRESSION, [Keyword.COMMA, EXPRESSION])
SUBROUTINE_CALL = {
(Keyword.IDENTIFIER, Keyword.PARAN_OPEN): [
EXPRESSIONLIST,
Keyword.PARAN_CLOSE,
],
(Keyword.IDENTIFIER, Keyword.DOT): [
Keyword.IDENTIFIER,
Keyword.PARAN_OPEN,
EXPRESSIONLIST,
Keyword.PARAN_CLOSE
]
}
STATEMENTS = {
(Keyword.LET): [Keyword.IDENTIFIER, (Keyword.SQUARE_OPEN, EXPRESSION, Keyword.SQUARE_CLOSE)],
(Keyword.IF): [
Keyword.PARAN_OPEN,
EXPRESSION,
Keyword.PARAN_CLOSE,
Keyword.BRACE_OPEN,
lambda:STATEMENTS,
Keyword.BRACE_CLOSE,
( Keyword.ELSE, Keyword.BRACE_OPEN, lambda:STATEMENTS, Keyword.BRACE_CLOSE)
],
(Keyword.WHILE): [
Keyword.PARAN_OPEN,
EXPRESSION,
Keyword.PARAN_CLOSE,
Keyword.BRACE_OPEN,
lambda:STATEMENTS,
Keyword.BRACE_CLOSE,
],
(Keyword.DO): SUBROUTINE_CALL,
(Keyword.RETURN): [(EXPRESSION), Keyword.SEMICOLON]
}
SUBROUTINEDEC = [
# (constructor | function | method) (void | type) subRoutineName '(' parameterList ')'
# subroutineBody
Keyword.CONSTRUCTOR | Keyword.FUNCTION | Keyword.METHOD,
Keyword.VOID | TYPE,
Keyword.IDENTIFIER,
Keyword.PARAN_OPEN,
# Parameter List =
# (
# (type varName) (, type varName)*
# )?
# we use tuples for zero OR one of a sequence
(
TYPE,
Keyword.IDENTIFIER,
[Keyword.COMMA, TYPE, Keyword.IDENTIFIER]
),
Keyword.PARAN_CLOSE,
# Subroutine Body {
Keyword.BRACE_OPEN,
# One or more variable declarations
# `var type varName (, varName)* ;`
[
Keyword.VAR,
TYPE,
Keyword.IDENTIFIER,
[Keyword.COMMA, Keyword.IDENTIFIER],
Keyword.SEMICOLON
],
STATEMENTS,
Keyword.BRACE_CLOSE,
]
CLASSVARDEC = [
# static|field type (, name)* ;
Keyword.STATIC | Keyword.FIELD,
TYPE,
[Keyword.COMMA, Keyword.IDENTIFIER],
Keyword.SEMICOLON
]
GRAMMAR = [
# class className {
Keyword.CLASS,
Keyword.IDENTIFIER,
Keyword.BRACE_OPEN,
# class Variable Declarations (one or more) = list
CLASSVARDEC,
# subroutine declarations (one or more) = list
SUBROUTINEDEC,
# }
Keyword.BRACE_CLOSE
]
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