def create_grammar(self):
symobject = SymbolObject(ls_grammar.langlet_id)
R = [' '.join([g[1] for g in R1]).strip() for R1 in self.rules]
symobject.create(R)
self.langlet.parse_symbol = symobject
self.nfagenerator = NFAGenerator(self.langlet, "Parser")
self.nfagenerator.create_all("\n".join(R)+"\n")
if self.nfagenerator.nfas:
self.nfagenerator.derive_properties()
self.nfagenerator.expand_nfas()
def create_bnf_langlet(bnf_grammar_file, lexer_file):
'''
Construct an ad-hoc langlet from a BNF grammar file.
'''
# parser-rules
cst = bnfreader.parse_file(bnf_grammar_file)
parser_rules = []
# do some normalization of rules of the grammar file
for rule in find_all(cst, bnfreader.symbol.rule):
ls_rule = " ".join(bnfreader.unparse(rule)[:-1].split()) + "\n"
parser_rules.append(ls_rule)
bnf_grammar = "".join(parser_rules)
langlet_id = 1000 * 100
parse_symbol = SymbolObject(langlet_id)
parse_symbol.create(parser_rules)
# lexer-rules
with open(lexer_file) as f_lex:
lexer_rules = ls_grammar.unparse(ls_grammar.parse(
f_lex.read())).split("\n")
lex_symbol = SymbolObject(langlet_id, 100)
lex_symbol.create(lexer_rules)
# create NFAs but don't compute properties. This won't work because
# left recursion prevents first-sets ( reachables ) to be derived.
langlet = LangletObject(langlet_id, parse_symbol, lex_symbol)
nfagen = NFAGenerator(langlet)
nfas = nfagen.create_all(bnf_grammar)
langlet.nfas = nfas
langlet.keywords = nfagen.keywords
return langlet
def create_grammar(self, report=False, expansion=True):
symobject = SymbolObject(self.langlet.langlet_id)
R = [' '.join([g[1] for g in R1]).strip() for R1 in self.rules]
symobject.create(R)
self.langlet.parse_symbol = self.langlet.symbol = symobject
self.nfagenerator = NFAGenerator(self.langlet, "Parser")
self.grammar = "\n".join(R) + "\n"
# print grammar
self.nfagenerator.create_all(self.grammar)
if self.nfagenerator.nfas:
self.nfagenerator.derive_properties()
if expansion:
self.nfagenerator.expand_nfas(report=report)
self.langlet.parse_nfa = self.nfagenerator.nfadata
self.langlet.keywords = self.langlet.parse_nfa.keywords
def create_grammar(self, report = False, expansion = True):
symobject = SymbolObject(self.langlet.langlet_id)
R = [' '.join([g[1] for g in R1]).strip() for R1 in self.rules]
symobject.create(R)
self.langlet.parse_symbol = self.langlet.symbol = symobject
self.nfagenerator = NFAGenerator(self.langlet, "Parser")
self.grammar = "\n".join(R)+"\n"
# print grammar
self.nfagenerator.create_all(self.grammar)
if self.nfagenerator.nfas:
self.nfagenerator.derive_properties()
if expansion:
self.nfagenerator.expand_nfas(report = report)
self.langlet.parse_nfa = self.nfagenerator.nfadata
self.langlet.keywords = self.langlet.parse_nfa.keywords
def create_bnf_langlet(bnf_grammar_file, lexer_file):
'''
Construct an ad-hoc langlet from a BNF grammar file.
'''
# parser-rules
cst = bnfreader.parse_file(bnf_grammar_file)
parser_rules = []
# do some normalization of rules of the grammar file
for rule in find_all(cst, bnfreader.symbol.rule):
ls_rule = " ".join(bnfreader.unparse(rule)[:-1].split())+"\n"
parser_rules.append(ls_rule)
bnf_grammar = "".join(parser_rules)
langlet_id = 1000*100
parse_symbol = SymbolObject(langlet_id)
parse_symbol.create(parser_rules)
# lexer-rules
with open(lexer_file) as f_lex:
lexer_rules = ls_grammar.unparse(ls_grammar.parse(f_lex.read())).split("\n")
lex_symbol = SymbolObject(langlet_id, 100)
lex_symbol.create(lexer_rules)
# create NFAs but don't compute properties. This won't work because
# left recursion prevents first-sets ( reachables ) to be derived.
langlet = LangletObject(langlet_id, parse_symbol, lex_symbol)
nfagen = NFAGenerator(langlet)
nfas = nfagen.create_all(bnf_grammar)
langlet.nfas = nfas
langlet.keywords = nfagen.keywords
return langlet