def terminal(self, text):
"""terminal = '"' . (printable - '"') + . '"'
| "'" . (printable - "'") + . "'" ;"""
self._attempting(text)
return alternation([
concatenation([
'"',
one_or_more(
exclusion(
self.printable,
'"'
),
ignore_whitespace=False
),
'"',
], ignore_whitespace=False),
concatenation([
"'",
one_or_more(
exclusion(
self.printable,
"'"
),
ignore_whitespace=False
),
"'",
], ignore_whitespace=False),
])(text).compressed(TokenType.terminal)
def number(self, text):
"""number = ["-"] . ("0" | digit - "0" . {digit}) . ["." . digit +] ;"""
self._attempting(text)
return concatenation([
option(
"-"
),
alternation([
"0",
concatenation([
exclusion(
self.digit,
"0"
),
zero_or_more(
self.digit,
ignore_whitespace=False
),
], ignore_whitespace=False),
]),
option(
concatenation([
".",
one_or_more(
self.digit,
ignore_whitespace=False
),
], ignore_whitespace=False)
),
], ignore_whitespace=False)(text).compressed(TokenType.number)
def test_concatenation(self):
c0 = P.concatenation(["a", "b", "c"], ignore_whitespace=True)
t0 = "abc"
n0 = c0(t0)
self.assertEqual(n0.node_type, P.ParseNodeType.concatenation)
self.assertFalse(n0.is_value)
self.assertEqual(n0.position, -len(t0))
self.assertEqual(len(n0.children), 3)
self.assertEqual(len(n0), 3)
with self.assertRaises(P.DeadEnd):
c0("bcd")
t1 = """ a\tb\nc"""
n1 = c0(t1)
# The position excludes skipped whitespace.
self.assertEqual(n1.position, -len(t1) + 1)
self.assertEqual(len(n1), 3)
self.assertEqual(n1.consumed, 6)
c1 = P.concatenation(["a", "b", "c"], ignore_whitespace=False)
n2 = c1(t0)
self.assertEqual(len(n2.children), 3)
# c1 raises on t1 because t1 has whitespace but c1 doesn't ignore whitespace.
with self.assertRaises(P.DeadEnd):
c1(t1)
def function_call(self, text):
"""function_call = function_name . "(" , [function_args] , ")" ;"""
self._attempting(text)
return concatenation([
self.function_name,
concatenation([
"(",
option(
self.function_args
),
")",
], ignore_whitespace=True),
], ignore_whitespace=False)(text).retyped(TokenType.function_call)
def function_args(self, text):
"""function_args = expression , {"," , function_args} ;"""
self._attempting(text)
return concatenation([
self.expression,
zero_or_more(
concatenation([
",",
self.function_args,
], ignore_whitespace=True),
ignore_whitespace=True
),
], ignore_whitespace=True)(text)
def switch_subject(self, text):
"""switch_subject = "switch" , expression ;"""
self._attempting(text)
return concatenation([
"switch",
self.expression,
], ignore_whitespace=True)(text).retyped(TokenType.switch_subject)
def grouping_group(self, text):
"""grouping_group = "(" , expression , ")" ;"""
self._attempting(text)
return concatenation([
"(",
self.expression,
")",
], ignore_whitespace=True)(text).retyped(TokenType.grouping_group)
def subexpression(self, text):
"""subexpression = "(" , expression , ")" ;"""
self._attempting(text)
return concatenation([
"(",
self.expression,
")",
], ignore_whitespace=True)(text).retyped(TokenType.subexpression)
def special_handling(self, text):
"""special_handling = "?" , identifier , "?" ;"""
self._attempting(text)
return concatenation([
"?",
self.identifier,
"?",
], ignore_whitespace=True)(text).retyped(TokenType.special_handling)
def switch_default(self, text):
"""switch_default = "else" , ":" , expression ;"""
self._attempting(text)
return concatenation([
"else",
":",
self.expression,
], ignore_whitespace=True)(text).retyped(TokenType.switch_default)
def option_group(self, text):
"""option_group = "[" , expression , "]" ;"""
self._attempting(text)
return concatenation([
"[",
self.expression,
"]",
], ignore_whitespace=True)(text).retyped(TokenType.option_group)
def repetition_group(self, text):
"""repetition_group = "{" , expression , "}" ;"""
self._attempting(text)
return concatenation([
"{",
self.expression,
"}",
], ignore_whitespace=True)(text).retyped(TokenType.repetition_group)
def branch_else(self, text):
"""branch_else = "else" , ":" , expression ;"""
self._attempting(text)
return concatenation([
"else",
":",
self.expression,
], ignore_whitespace=True)(text).retyped(TokenType.branch_else)
def switch_case(self, text):
"""switch_case = "when" , expression , ":" , expression ;"""
self._attempting(text)
return concatenation([
"when",
self.expression,
":",
self.expression,
], ignore_whitespace=True)(text).retyped(TokenType.switch_case)
def rule(self, text):
"""rule = identifier , "=" , expression , ";" ;"""
self._attempting(text)
return concatenation([
self.identifier,
"=",
self.expression,
";",
], ignore_whitespace=True)(text).retyped(TokenType.rule)
def statement(self, text):
"""statement = comment | assignment , ";" ;"""
self._attempting(text)
return alternation([
self.comment,
concatenation([
self.assignment,
";",
], ignore_whitespace=True),
])(text)
def assignment(self, text):
"""assignment = variable , (":=" | "<-") , expression ;"""
self._attempting(text)
return concatenation([
self.variable,
alternation([
":=",
"<-",
]),
self.expression,
], ignore_whitespace=True)(text).retyped(TokenType.assignment)
def expression(self, text):
"""expression = {operator} , expression_terminal , {operator + , expression} ;"""
self._attempting(text)
return concatenation([
zero_or_more(
self.operator,
ignore_whitespace=True
),
self.expression_terminal,
zero_or_more(
concatenation([
one_or_more(
self.operator,
ignore_whitespace=True
),
self.expression,
], ignore_whitespace=True),
ignore_whitespace=True
),
], ignore_whitespace=True)(text).retyped(TokenType.expression)
def return_statement(self, text):
"""return_statement = ["return"] , expression , [";"] ;"""
self._attempting(text)
return concatenation([
option(
"return"
),
self.expression,
option(
";"
),
], ignore_whitespace=True)(text).retyped(TokenType.return_statement)
def branch(self, text):
"""branch = branch_if , {branch_elif} , branch_else ;
b"""
self._attempting(text)
return concatenation([
self.branch_if,
zero_or_more(
self.branch_elif,
ignore_whitespace=True
),
self.branch_else,
], ignore_whitespace=True)(text).retyped(TokenType.branch)
def string(self, text):
"""string = '"' . {double_string_char} . '"'
| "'" . {single_string_char} . "'" ;"""
self._attempting(text)
return alternation([
concatenation([
'"',
zero_or_more(
self.double_string_char,
ignore_whitespace=False
),
'"',
], ignore_whitespace=False),
concatenation([
"'",
zero_or_more(
self.single_string_char,
ignore_whitespace=False
),
"'",
], ignore_whitespace=False),
])(text).compressed(TokenType.string)
def eol(self, text):
"""eol = { whitespace - "\n" } . "\n" ;"""
self._attempting(text)
return concatenation([
zero_or_more(
exclusion(
self.whitespace,
"\n"
),
ignore_whitespace=False
),
"\n",
], ignore_whitespace=False)(text)
def double_string_char(self, text):
"""double_string_char = "\\" . all_characters - '"'
| "\" . '"'
| all_characters - '"' ;"""
self._attempting(text)
return alternation([
concatenation([
"\\\\",
exclusion(
self.all_characters,
'"'
),
], ignore_whitespace=False),
concatenation([
"\\",
'"',
], ignore_whitespace=False),
exclusion(
self.all_characters,
'"'
),
])(text).retyped(TokenType.double_string_char)
def single_string_char(self, text):
"""single_string_char = "\\" . all_characters - "'"
| "\" . "'"
| all_characters - "'" ;"""
self._attempting(text)
return alternation([
concatenation([
"\\\\",
exclusion(
self.all_characters,
"'"
),
], ignore_whitespace=False),
concatenation([
"\\",
"'",
], ignore_whitespace=False),
exclusion(
self.all_characters,
"'"
),
])(text).retyped(TokenType.single_string_char)
def number(self, text):
"""number = digit - "0" . {digit} ;"""
self._attempting(text)
return concatenation([
exclusion(
self.digit,
"0"
),
zero_or_more(
self.digit,
ignore_whitespace=False
),
], ignore_whitespace=False)(text).compressed(TokenType.number)
def complex_identifier(self, text):
"""complex_identifier = "[" . (all_characters - "]") + . "]" ;"""
self._attempting(text)
return concatenation([
"[",
one_or_more(
exclusion(
self.all_characters,
"]"
),
ignore_whitespace=False
),
"]",
], ignore_whitespace=False)(text).retyped(TokenType.complex_identifier)
def comment(self, text):
"""comment = "/*" . {all_characters - "*" | "*" . all_characters - "/"} . "*/" ;"""
self._attempting(text)
return concatenation([
"/*",
zero_or_more(
alternation([
exclusion(
self.all_characters,
"*"
),
concatenation([
"*",
exclusion(
self.all_characters,
"/"
),
], ignore_whitespace=False),
]),
ignore_whitespace=False
),
"*/",
], ignore_whitespace=False)(text).compressed(TokenType.comment)
def directive(self, text):
"""directive = "#" . { all_characters - "\n" } . eol ;"""
self._attempting(text)
return concatenation([
"#",
zero_or_more(
exclusion(
self.all_characters,
"\n"
),
ignore_whitespace=False
),
self.eol,
], ignore_whitespace=False)(text).compressed(TokenType.directive)
def comment(self, text):
"""comment = "(*" . {printable - "*" | "*" . printable - ")"} . "*)" ;"""
self._attempting(text)
return concatenation([
"(*",
zero_or_more(
alternation([
exclusion(
self.printable,
"*"
),
concatenation([
"*",
exclusion(
self.printable,
")"
),
], ignore_whitespace=False),
]),
ignore_whitespace=False
),
"*)",
], ignore_whitespace=False)(text).compressed(TokenType.comment)
def switch(self, text):
"""switch = switch_subject , switch_case + , [switch_default] ;
s"""
self._attempting(text)
return concatenation([
self.switch_subject,
one_or_more(
self.switch_case,
ignore_whitespace=True
),
option(
self.switch_default
),
], ignore_whitespace=True)(text).retyped(TokenType.switch)
