def failToken(s):
"""
pyparsing hack to give better error messages,
"a or b expected" rather than "b expected".
"""
t = NoMatch()
t.setName(s)
return t
def get_match_first(lits, parseAction=None):
el = MatchFirst(NoMatch())
for lit in lits:
el = el.__ior__(lit)
if parseAction:
el.setParseAction(parseAction)
return el
def sreduce(f, l):
''' Same as reduce, but handle len 1 and len 0 lists sensibly '''
if len(l) == 0:
return NoMatch()
if len(l) == 1:
return l[0]
return reduce(f, l)
class Markup:
def __init__(self, tokens_list):
self._markup = NoMatch()
for token in tokens_list:
self._markup |= token
def transformString(self, text):
return self._markup.transformString(text)
def make_operations(operand, operators, group_start="(", group_end=")"):
"""
Build the Pyparsing grammar for the ``operators`` and return it.
:param operand: The Pyparsing grammar for the operand to be handled by
the ``operators``.
:param operators: List of quintuples that define the properties of every
operator.
The order of the ``operators`` describe the precedence of the operators.
Each tuple in ``operators`` are made up of the following five elements,
which define the operator:
- The Pyparsing expression for the operator.
- The arity of the operator (1 or 2).
- The associativity of the operator ("left" or "right"), if it's a binary
operation; otherwise ``None``.
- The notation of the operator (prefix, postfix or infix), if it's a binary
one.
- Whether the left-hand operand should be the master operand. If ``False``,
the left- and right-hand operands will be the slave and master ones.
- The parse action of the operator.
The parse actions for unary operations will receive the named results for
the ``operator`` and the ``operand``, while those for binary operations will
receive the named results for the ``operator`` and the ``master_operand``
and the ``slave_operand``.
The code for the operatorPrecedence() function in Pyparsing was used as an
starting point to make this function.
"""
operation = Forward()
group_start = Suppress(group_start)
group_end = Suppress(group_end)
last_expression = operand | (group_start + operation + group_end)
# The "previous_operators" variable represents the expressions for the
# previous operators, so it can be used to prevent wrong matches of
# operators when a higher level operator was expected. This would happen
# when the string of an operator represents the starting characters of
# a higher level operator. See Bug #397807.
previous_operators = NoMatch()
for (operator_expr, arity, assoc, notation, master_left, pa) in operators:
final_operator = ~previous_operators + operator_expr
new_expression = _append_operation(operand, last_expression,
final_operator,
arity, assoc.lower(),
notation.lower(), master_left, pa)
last_expression = new_expression
# Updating the list of previous operators, so they won't be matched in
# higher-level operations:
previous_operators = previous_operators | operator_expr
operation << last_expression
return operation
def parse_imp(input):
# Grammar:
#
# <expr> ::= <integer>
# true
# false
# <identifier>
#
# <fact> ::= relation(constant, ...).
#
# <rule> ::= name(constant, ... ) :- name(constant, ...), ... .
#
idChars = alphas + "_+*!=<>"
pNAME = Word(idChars, idChars + "0123456789")
pRELATION = pNAME + \
"(" + Group(pNAME + ZeroOrMore(Suppress(",") + pNAME)) + ")"
pRELATION.setParseAction(lambda result: (result[0], result[2]))
pDECL_RELATION = pRELATION + "."
pDECL_RELATION.setParseAction(lambda result: result[0])
pRULE = pRELATION + ":-" + \
Group(pRELATION + ZeroOrMore(Suppress(",") + pRELATION)) + "."
pRULE.setParseAction(lambda result: (result[0], result[2]))
pFACT = (pDECL_RELATION ^ NoMatch())
pQUERY = pRELATION + "?"
pQUERY.setParseAction(lambda result: (result[0][0], result[0][1]))
pTOP_QUERY = pQUERY.copy()
pTOP_QUERY.setParseAction(lambda result: {
"result": "query",
"stmt": result[0]
})
pTOP_RULE = pRULE.copy()
pTOP_RULE.setParseAction(lambda result: {"result": "rule", "rule": result})
pTOP_FACT = pFACT.copy()
pTOP_FACT.setParseAction(lambda result: {
"result": "fact",
"decl": result[0]
})
pQUIT = Keyword("#quit")
pQUIT.setParseAction(lambda result: {"result": "quit"})
pENV = Keyword("#env")
pENV.setParseAction(lambda result: {"result": "env"})
pTOP = (pQUIT ^ pENV ^ pTOP_RULE ^ pTOP_FACT ^ pTOP_QUERY)
result = pTOP.parseString(input)[0]
return result # the first element of the result is the expression
def concatenate(tokenlist):
"""
Склеить несколько токенов из списка
"""
if len(tokenlist) == 0:
return NoMatch()
result = tokenlist[0]
for token in tokenlist[1:]:
result |= token
return result
def update_bind_expr(self):
self.print_bind_forward << reduce(self._accumulator,
self.current_bind_exprs.values(),
NoMatch()) + StringEnd()
return Group(
Suppress(backslash) + Literal(key) + Suppress(White()) +
CharsNotIn(u' \n\t\\') + Suppress(White()))
#
# DEFINE GRAMMAR
#
#phrase = Word( alphas + u"-.,!? —–‘“”’;:()'\"[]/&%=*…{}" + nums )
phrase = CharsNotIn(u"\n\\")
backslash = Literal(u"\\")
plus = Literal(u"+")
textBlock = Group(
Optional(NoMatch(), u"text") + Optional(Suppress(newline)) + phrase)
unknown = Group(
Optional(NoMatch(), u"unknown") + Suppress(backslash) +
CharsNotIn(u' \n\t\\'))
knownTokens = []
simpleTokens = [
'p', 'pi', 'b', 'q', 'q1', 'q2', 'q3', 'nb', 'm', 'li', 'd', 'sp', 'mi',
'pb', 'ip', 'iot', 'io', 'io1', 'io2', 'ip'
]
for st in simpleTokens:
knownTokens.append(usfmToken(st))
numberTokens = ['c', 'v']
for nt in numberTokens:
def _getForbiddenToken(self):
return NoMatch()
Optional(value))
def usfmTokenNumber(key):
return Group(
Suppress(backslash) + Literal(key) + Suppress(White()) +
Word(nums + '-()') + Suppress(White()))
# define grammar
# phrase = Word( alphas + "-.,!? —–‘“”’;:()'\"[]/&%=*…{}" + nums )
phrase = CharsNotIn("\n\\")
backslash = Literal("\\")
plus = Literal("+")
textBlock = Group(Optional(NoMatch(), "text") + phrase)
unknown = Group(
Optional(NoMatch(), "unknown") + Suppress(backslash) +
CharsNotIn(u' \n\t\\'))
escape = usfmTokenValue("\\", phrase)
id_token = usfmTokenValue("id", phrase)
ide = usfmTokenValue("ide", phrase)
sts = usfmTokenValue("sts", phrase)
h = usfmTokenValue("h", phrase)
mt = usfmTokenValue("mt", phrase)
mt1 = usfmTokenValue("mt1", phrase)
mt2 = usfmTokenValue("mt2", phrase)
mt3 = usfmTokenValue("mt3", phrase)
ms = usfmTokenValue("ms", phrase)
def usfmTokenValue(key, value):
return Group(Suppress(backslash) + Literal(key) + Suppress(White()) + Optional(value))
def usfmTokenNumber(key):
return Group(Suppress(backslash) + Literal(key) + Suppress(White()) + Word(nums + '-()') + Suppress(White()))
# define grammar
# phrase = Word( alphas + "-.,!? —–‘“”’;:()'\"[]/&%=*…{}" + nums )
phrase = CharsNotIn("\n\\")
backslash = Literal("\\")
plus = Literal("+")
textBlock = Group(Optional(NoMatch(), "text") + phrase)
unknown = Group(Optional(NoMatch(), "unknown") + Suppress(backslash) + CharsNotIn(u' \n\t\\'))
id_token = usfmTokenValue("id", phrase)
ide = usfmTokenValue("ide", phrase)
sts = usfmTokenValue("sts", phrase)
h = usfmTokenValue("h", phrase)
mt = usfmTokenValue("mt", phrase)
mt1 = usfmTokenValue("mt1", phrase)
mt2 = usfmTokenValue("mt2", phrase)
mt3 = usfmTokenValue("mt3", phrase)
ms = usfmTokenValue("ms", phrase)
ms1 = usfmTokenValue("ms1", phrase)
ms2 = usfmTokenValue("ms2", phrase)
mr = usfmTokenValue("mr", phrase)
def parse_imp(input):
# parse a string into an element of the abstract representation
# Grammar:
#
# <expr> ::= <integer>
# true
# false
# <identifier>
# ( if <expr> <expr> <expr> )
# ( function ( <name ... ) <expr> )
# ( <expr> <expr> ... )
#
# <decl> ::= var name = expr ;
#
# <stmt> ::= if <expr> <stmt> else <stmt>
# while <expr> <stmt>
# name <- <expr> ;
# print <expr> ;
# <block>
#
# <block> ::= { <decl> ... <stmt> ... }
#
# <toplevel> ::= <decl>
# <stmt>
#
idChars = alphas + "_+*-/?!=<>"
pIDENTIFIER = Word(idChars, idChars + "0123456789")
#### NOTE THE DIFFERENCE
pIDENTIFIER.setParseAction(
lambda result: EPrimCall(oper_deref, [EId(result[0])]))
pIDENTIFIERS = ZeroOrMore(pIDENTIFIER)
pIDENTIFIERS.setParseAction(lambda result: [result])
# A name is like an identifier but it does not return an EId...
pNAME = Word(idChars, idChars + "0123456789")
pNAMES = ZeroOrMore(pNAME)
pNAMES.setParseAction(lambda result: [result])
pINTEGER = Word("0123456789")
pINTEGER.setParseAction(lambda result: EValue(VInteger(int(result[0]))))
pBOOLEAN = Keyword("true") | Keyword("false")
pBOOLEAN.setParseAction(
lambda result: EValue(VBoolean(result[0] == "true")))
def escapeString(inStr):
inStr = inStr[1:-1]
outStr = ""
i = 0
while (i < len(inStr) - 1):
if (inStr[i] == '\\'):
if (inStr[i + 1] == '\\' or inStr[i + 1] == '\"'):
i += 1
outStr += inStr[i]
i += 1
outStr += inStr[-1]
return outStr
pSTRING = quotedString.copy()
pSTRING.setParseAction(
lambda result: EValue(VString(escapeString(result[0]))))
pEXPR = Forward()
pEXPRS = ZeroOrMore(pEXPR)
pEXPRS.setParseAction(lambda result: [result])
pIF = "(" + Keyword("if") + pEXPR + pEXPR + pEXPR + ")"
pIF.setParseAction(lambda result: EIf(result[2], result[3], result[4]))
def mkFunBody(params, body):
bindings = [(p, ERefCell(EId(p))) for p in params]
return ELet(bindings, body)
pFUN = "(" + Keyword("function") + "(" + pNAMES + ")" + pEXPR + ")"
pFUN.setParseAction(
lambda result: EFunction(result[3], mkFunBody(result[3], result[5])))
pBINDING = "(" + pNAME + pEXPR + ")"
pBINDING.setParseAction(lambda result: (result[1], result[2]))
pBINDINGS = ZeroOrMore(pBINDING)
pBINDINGS.setParseAction(lambda result: [result])
pCALL = "(" + pEXPR + pEXPRS + ")"
pCALL.setParseAction(lambda result: ECall(result[1], result[2]))
pEXPR << (pINTEGER | pBOOLEAN | pSTRING | pIDENTIFIER | pIF | pFUN | pCALL)
pDECL_VAR = "var" + pNAME + "=" + pEXPR + ";"
pDECL_VAR.setParseAction(lambda result: (result[1], result[3]))
pDECL_ARRAY = "var" + pNAME + "<-" + "(" + "new-array" + pEXPR + ")" + ";"
pDECL_ARRAY.setParseAction(lambda result: (result[1], EArray(result[5])))
# hack to get pDECL to match only PDECL_VAR (but still leave room
# to add to pDECL later)
pDECL = (pDECL_VAR | pDECL_ARRAY | NoMatch())
pDECLS = ZeroOrMore(pDECL)
pDECLS.setParseAction(lambda result: [result])
pSTMT = Forward()
pSTMT_IF_1 = "if" + pEXPR + pSTMT + "else" + pSTMT
pSTMT_IF_1.setParseAction(
lambda result: EIf(result[1], result[2], result[4]))
pSTMT_IF_2 = "if" + pEXPR + pSTMT
pSTMT_IF_2.setParseAction(
lambda result: EIf(result[1], result[2], EValue(VBoolean(True))))
pSTMT_WHILE = "while" + pEXPR + pSTMT
pSTMT_WHILE.setParseAction(lambda result: EWhile(result[1], result[2]))
pSTMT_PRINT = "print" + pEXPR + ";"
pSTMT_PRINT.setParseAction(
lambda result: EPrimCall(oper_print, [result[1]]))
pSTMT_UPDATE = pNAME + "<-" + pEXPR + ";"
pSTMT_UPDATE.setParseAction(
lambda result: EPrimCall(oper_update, [EId(result[0]), result[2]]))
pSTMTARR_UPDATE = pNAME + "[" + pEXPR + "]" + "<-" + pEXPR + ";"
pSTMTARR_UPDATE.setParseAction(lambda result: EPrimCall(
oper_update_arr, [EId(result[0]), result[5], result[2]]))
# pSTMT_FOR = "for" + "(" + pSTMT_UPDATE + pEXPR + ";" + pSTMT_UPDATE + ")" + pSTMT
# pSTMT_FOR.setParseAction(lambda result: EDo([result[2],EWhile(result[3], EDo([result[7],result[5]])) ] ))
pSTMT_FOR = "for" + pSTMT_UPDATE + pEXPR + ";" + pSTMT_UPDATE + pSTMT
pSTMT_FOR.setParseAction(lambda result: EDo(
[result[1], EWhile(result[2], EDo([result[5], result[4]]))]))
pSTMTS = ZeroOrMore(pSTMT)
pSTMTS.setParseAction(lambda result: [result])
def mkBlock(decls, stmts):
bindings = [(n, ERefCell(expr)) for (n, expr) in decls]
return ELet(bindings, EDo(stmts))
pSTMT_BLOCK = "{" + pDECLS + pSTMTS + "}"
pSTMT_BLOCK.setParseAction(lambda result: mkBlock(result[1], result[2]))
pDEFPROC = "procedure" + pNAME + "(" + pNAMES + ")" + pSTMT
pDEFPROC.setParseAction(
lambda result: {
"result":
"procedure",
"proc":
(result[1], EProcedure(result[3], mkFunBody(result[3], result[5])))
})
pSTMT_PROC = pIDENTIFIER + "(" + pEXPRS + ")" + ";"
pSTMT_PROC.setParseAction(lambda result: EProcCall(result[0], result[2]))
pWITH = "(" + Keyword(
"with") + pIDENTIFIER + pIDENTIFIER + "(" + pEXPRS + ")" + ")"
pWITH.setParseAction(lambda result: EWith(result[2], result[3], result[5]))
pNOTIMPLEMENTED = Keyword("<>")
pNOTIMPLEMENTED.setParseAction(lambda result: ENotImplemented())
pSTMT << (pSTMT_IF_1 | pSTMT_IF_2 | pSTMT_WHILE | pSTMT_PRINT | pSTMT_FOR
| pSTMT_UPDATE | pSTMTARR_UPDATE | pSTMT_BLOCK | pSTMT_PROC
| pWITH)
# can't attach a parse action to pSTMT because of recursion, so let's duplicate the parser
pTOP_STMT = pSTMT.copy()
pTOP_STMT.setParseAction(lambda result: {
"result": "statement",
"stmt": result[0]
})
pTOP_DECL = pDECL.copy()
pTOP_DECL.setParseAction(lambda result: {
"result": "declaration",
"decl": result[0]
})
pABSTRACT = "#abs" + pSTMT
pABSTRACT.setParseAction(lambda result: {
"result": "abstract",
"stmt": result[1]
})
pQUIT = Keyword("#quit")
pQUIT.setParseAction(lambda result: {"result": "quit"})
pDEFFUN = "(" + pNAME + "(" + pNAMES + ")" + pSTMT + ")"
pDEFFUN.setParseAction(lambda result: (result[
1], EProcedure(result[3], mkFunBody(result[3], result[5]))))
pDEFABSFUN = "(" + pNAME + "(" + pNAMES + ")" + pNOTIMPLEMENTED + ")"
pDEFABSFUN.setParseAction(lambda result: (result[1], ENotImplemented()))
pDEFFUNS = ZeroOrMore((pDEFFUN | pDEFABSFUN))
pDEFFUNS.setParseAction(lambda result: [result])
pTEMPLATE = Keyword(
"class"
) + "(" + pNAME + pIDENTIFIER + "(" + pNAMES + ")" + "(" + pIDENTIFIERS + ")" + "(" + pDEFFUNS + ")" + ")"
pTEMPLATE.setParseAction(
lambda result: {
"result":
"template",
"temp": (result[2],
ETemplate(False, result[2], result[3], result[5], result[
8], result[11]))
})
pABSTEMPLATE = Keyword(
"absclass"
) + "(" + pNAME + pIDENTIFIER + "(" + pNAMES + ")" + "(" + pIDENTIFIERS + ")" + "(" + pDEFFUNS + ")" + ")"
pABSTEMPLATE.setParseAction(
lambda result: {
"result":
"template",
"temp": (result[2],
ETemplate(True, result[2], result[3], result[5], result[
8], result[11]))
})
pNEWOBJ = Keyword("new") + pIDENTIFIER + "(" + pEXPRS + ")"
pNEWOBJ.setParseAction(lambda result: EObject(result[1], result[3]))
pOBJASS = Keyword("obj") + pIDENTIFIER + pNAME + "=" + pNEWOBJ
pOBJASS.setParseAction(
lambda result: {
"result": "objectassignment",
"assignment": (result[2], EObjectBinding(result[1], result[4]))
})
pMULTI = Keyword("#multi")
pMULTI.setParseAction(lambda result: {"result": "multi"})
pTOP = (pQUIT | pABSTRACT | pTOP_DECL | pTOP_STMT | pDEFPROC | pTEMPLATE
| pOBJASS | pMULTI | pABSTEMPLATE)
result = pTOP.parseString(input)[0]
return result # the first element of the result is the expression
def create(self, pa):
def itercalls():
def getbrackets(blankpa, scalarpa):
optblank = _getoptblank(blankpa, '')
return Literal(o) + ZeroOrMore(optblank + _getarg(callchain, scalarpa, c)) + optblank + Literal(c)
for o, c in self.bracketpairs:
yield (Suppress(Regex("[$](?:lit|')")) + Suppress(o) + Regex("[^%s]*" % re.escape(c)) + Suppress(c)).setParseAction(Text.pa)
yield (Suppress(Regex('[$](?:pass|[.])')) + getbrackets(Text.pa, Text.pa)).setParseAction(self._bracketspa)
yield (Suppress('$') + self.identifier + getbrackets(Blank.pa, AnyScalar.pa)).setParseAction(_principalcallpa)
yield (Suppress('$') + self.identifier + callchain).setParseAction(_additionalcallpa)
optblank = _getoptblank(Blank.pa, self.boundarychars)
callchain = Forward()
callchain << MatchFirst(itercalls()).leaveWhitespace()
return reduce(operator.add, [
self.ormorecls(optblank + _getarg(callchain, self.scalarpa, self.boundarychars)),
optblank,
Optional(Regex("[%s]+" % re.escape(self.boundarychars)).leaveWhitespace().setParseAction(Boundary.pa) if self.boundarychars else NoMatch()),
]).setParseAction(pa)
def __init__(self, tokens_list):
self._markup = NoMatch()
for token in tokens_list:
self._markup |= token
def reinit_exprs(self):
command = reduce(lambda acc, e: acc | e[1], self.commands, NoMatch())
self.dm_expr = self.dm_expr_head + command
self.expr = self.expr_head + command
def parse_imp (input):
# parse a string into an element of the abstract representation
# Grammar:
#
# <expr> ::= <integer>
# true
# false
# <identifier>
# ( if <expr> <expr> <expr> )
# ( function ( <name ... ) <expr> )
# ( <expr> <expr> ... )
#
# <decl> ::= var name = expr ;
#
# <stmt> ::= if <expr> <stmt> else <stmt>
# while <expr> <stmt>
# name <- <expr> ;
# print <expr> ;
# <block>
#
# <block> ::= { <decl> ... <stmt> ... }
#
# <toplevel> ::= <decl>
# <stmt>
#
idChars = alphas+"_+*-?!=<>+"
QUOTE = Literal('"')
INTERNAL_QUOTE = QUOTE.copy().leaveWhitespace()
pIDENTIFIER = Word(idChars, idChars+"0123456789")
#### NOTE THE DIFFERENCE
pIDENTIFIER.setParseAction(lambda result: EPrimCall(oper_deref,[EId(result[0])]))
# A name is like an identifier but it does not return an EId...
pNAME = Word(idChars,idChars+"0123456789") #| Keyword("&\"") | Keyword("&\'")
pNAMECON = "," + pNAME
pNAMECON.setParseAction(lambda result: result[1])
pNAMES = pNAME + ZeroOrMore(pNAMECON) | ZeroOrMore(pNAME)
pNAMES.setParseAction(lambda result: [result])
pINTEGER = Word("0123456789")
pINTEGER.setParseAction(lambda result: EValue(VInteger(int(result[0]))))
QUOTE = Literal("&\"") | Literal("&\'")
pSTRINGSTART = Literal('"') + ZeroOrMore(Word(" ")).leaveWhitespace()
pSTRINGSTART.setParseAction(lambda result: result[1:])
pSTRING = pSTRINGSTART + ZeroOrMore(Combine( Word(idChars+"0123456789'"+" ") | QUOTE)) + Literal('"')
pSTRING.setParseAction(lambda result: EValue(VString(str(result[:-1]))))
pBOOLEAN = Keyword("true") | Keyword("false")
pBOOLEAN.setParseAction(lambda result: EValue(VBoolean(result[0]=="true")))
pEXPR = Forward()
pEXPR2 = Forward()
pSTMT_BLOCK = Forward()
pSTMT = Forward()
pEXPRS = ZeroOrMore(pEXPR2)
pEXPRS.setParseAction(lambda result: [result])
pIF = pEXPR + Keyword("?") + pEXPR + Keyword(':') + pEXPR
pIF.setParseAction(lambda result: EIf(result[0], result[2], result[4]))
def mkFunBody (params,body):
bindings = [ (p,ERefCell(EId(p))) for p in params ]
return ELet(bindings,body)
def mkLetBody (bindings,body):
bindings = [ (p[0],ERefCell(p[1])) for p in bindings ]
return ELet(bindings,body)
def multiCallHelper(result, start, i, length):
if i < length:
start = ECall(result[1][i][0], [result[1][i][1], start])
multiCallHelper(result, start, i + 1, length)
return start
def multiCall(result):
start = ECall(result[1][0][0], [result[0], result[1][0][1]])
return multiCallHelper(result, start, 1, len(result[1]))
def eFunHelper(variables, expression):
if len(variables) == 1:
return EFunction(variables[0], expression)
else:
return EFunction(variables[0], eFunHelper(variables[1:], expression))
def eFunName(result):
varName = result[1]
variables = result[3]
expression = result[-1]
print variables, expression
return EFunction(variables, expression, varName)
pFUN = Keyword("fun") + "(" + pNAMES + ")" + pSTMT
pFUN.setParseAction(lambda result: EFunction(result[2],mkFunBody(result[2],result[4])))
pFUNR = Keyword("fun") + pNAME + "(" + pNAMES + ")" + pSTMT
# pFUNR.setParseAction(eFunName)
pFUNR.setParseAction(lambda result: EFunction(result[3],mkFunBody(result[3],result[5]), result[1]))
pEXPR2CAR = "," + pEXPR2
pEXPR2CAR.setParseAction(lambda result: result[1])
pEXPR2MULTIALL = pEXPR2 + ZeroOrMore(pEXPR2CAR) | ZeroOrMore(pEXPR2)
pEXPR2MULTIALL.setParseAction(lambda result: [result])
pFUNCALL = pEXPR + "(" + pEXPR2MULTIALL + ")"
pFUNCALL.setParseAction(lambda result: ECall(result[0], result[2]))
pBINDINGCAR = "," + pNAME + "=" + pEXPR2
pBINDINGCAR.setParseAction(lambda result: (result[1], result[3]))
pBINDINGCON = pNAME + "=" + pEXPR2
pBINDINGCON.setParseAction(lambda result: (result[0], result[2]))
pBINDINGS = pBINDINGCON + ZeroOrMore(pBINDINGCAR)
pBINDINGS.setParseAction(lambda result: [result])
pLET = Keyword("let") + "(" + pBINDINGS + ")" + pEXPR2
pLET.setParseAction(lambda result: mkLetBody(result[2], result[4]))
pCALLG = pIDENTIFIER + pEXPR2
pCALLG.setParseAction(lambda result: (result[0], result[1]))
pCALL1S = OneOrMore(pCALLG)
pCALL1S.setParseAction(lambda result: [ result ])
pCALL = pEXPR + pCALL1S
pCALL.setParseAction(multiCall)
pCALL1 = pIDENTIFIER + pEXPR2
pCALL1.setParseAction(lambda result: ECall(result[0], [result[1]]))
pNOT = "not" + pEXPR2
pNOT.setParseAction(lambda result: EPrimCall(oper_not, [result[1]]))
pARRAYITEM = "," + pEXPR2
pARRAYITEM.setParseAction(lambda result: (result[1]))
pARRAYITEMS = ZeroOrMore(pARRAYITEM)
pARRAYITEMS.setParseAction(lambda result: [result])
pARRAY = "[" + ZeroOrMore(pEXPR2) + pARRAYITEMS + "]"
pARRAY.setParseAction(lambda result: EArray(result[1],result[2]))
pDICTPAIR = pNAME + ":" + pEXPR
pDICTPAIR.setParseAction(lambda result: (result[0],result[2]))
pDICTPAIRWITHCOMMA = "," + pNAME + ":" + pEXPR
pDICTPAIRWITHCOMMA.setParseAction(lambda result: (result[1],result[3]))
pDICTS = ZeroOrMore(pDICTPAIRWITHCOMMA)
pDICTS.setParseAction(lambda result: [ result ])
pDICT = "{" + pDICTPAIR + pDICTS + "}"
pDICT.setParseAction(lambda result:EDict(result[1],result[2]))
pEXPR2P = "(" + pEXPR2 + ")"
pEXPR2P.setParseAction(lambda result: result[1])
pACCESS = pNAME + "[" + pEXPR + "]"
pACCESS.setParseAction(lambda result: EPrimCall(oper_access_arr,[EId(result[0]),result[2]]))
pLEN = Keyword("len") + "(" + pNAME + ")"
pLEN.setParseAction(lambda result: EPrimCall(oper_len,[EId(result[2])]))
pEXPR << ( pEXPR2P | pINTEGER | pNOT | pARRAY | pACCESS | pDICT | pSTRING | pBOOLEAN | pIDENTIFIER | pCALL1 | pLEN )
pEXPR2 << ( pLET | pFUN | pFUNR | pFUNCALL | pIF | pCALL | pEXPR )
pDECL_VAR_E = "var" + pNAME + ";"
pDECL_VAR_E.setParseAction(lambda result: (result[1], EValue(VNone)))
pDECL_VAR = "var" + pNAME + "=" + pEXPR2 + ";"
pDECL_VAR.setParseAction(lambda result: (result[1],result[3]))
pDECL_PROCEDURE = "def" + pNAME + "(" + pNAMES + ")" + pSTMT
pDECL_PROCEDURE.setParseAction(lambda result: (result[1], EProcedure(result[3], mkFunBody(result[3], result[5]))))
# hack to get pDECL to match only PDECL_VAR (but still leave room
# to add to pDECL later)
pDECL = ( pDECL_VAR_E | pDECL_VAR | pDECL_PROCEDURE | NoMatch() | ";" )
pDECLS = ZeroOrMore(pDECL)
pDECLS.setParseAction(lambda result: [result])
pSTMT_IF_1 = "if (" + pEXPR2 + ")" + pSTMT + "else" + pSTMT
pSTMT_IF_1.setParseAction(lambda result: EIf(result[1],result[3],result[5]))
pSTMT_IF_2 = "if (" + pEXPR2 + ")" + pSTMT
pSTMT_IF_2.setParseAction(lambda result: EIf(result[1],result[3],EValue(VBoolean(True))))
pSTMT_WHILE = "while (" + pEXPR2 + ")" + pSTMT
pSTMT_WHILE.setParseAction(lambda result: EWhile(result[1],result[3]))
pSTMT_FOR = "for (" + pNAME + "in" + pEXPR2 + ")" + pSTMT
pSTMT_FOR.setParseAction(lambda result: EFor(result[1], result[3], result[5]))
pSTMT_PRINT_STMS = "," + pEXPR2
pSTMT_PRINT_STMS.setParseAction(lambda result: [ result[1] ])
pSTMT_PRINT_ZERO = ZeroOrMore(pSTMT_PRINT_STMS)
pSTMT_PRINT_ZERO.setParseAction(lambda result: [ result ])
def printStmEval(result):
newArray = []
newArray.append(result[1])
for i in result[2]:
newArray.append(i)
return EPrimCall(oper_print,newArray)
pSTMT_PRINT = "print" + pEXPR2 + pSTMT_PRINT_ZERO + ";"
pSTMT_PRINT.setParseAction(printStmEval)
pSTMT_UPDATE_ARR = pNAME + "[" + pEXPR +"]" + "=" + pEXPR + ";"
pSTMT_UPDATE_ARR.setParseAction(lambda result: EPrimCall(oper_update_arr,[EId(result[0]),result[2],result[5]]))
pSTMT_UPDATE = pNAME + "=" + pEXPR2 + ";"
pSTMT_UPDATE.setParseAction(lambda result: EPrimCall(oper_update,[EId(result[0]),result[2]]))
pSTMTS = ZeroOrMore(pSTMT)
pSTMTS.setParseAction(lambda result: [result])
def mkBlock (decls,stmts):
bindings = [ (n,ERefCell(expr)) for (n,expr) in decls ]
return ELet(bindings,EDo(stmts))
pSTMT_BLOCK = "{" + pDECLS + pSTMTS + "}"
pSTMT_BLOCK.setParseAction(lambda result: mkBlock(result[1],result[2]))
pSTMT_pEXPR2 = pEXPR2 + ";"
pSTMT_pEXPR2.setParseAction(lambda result: result[0])
pSTMT << ( pSTMT_IF_1 | pSTMT_IF_2 | pSTMT_WHILE | pSTMT_FOR | pSTMT_PRINT | pSTMT_UPDATE_ARR | pSTMT_UPDATE | pSTMT_BLOCK | pSTMT_pEXPR2 | pEXPR2 )
# can't attach a parse action to pSTMT because of recursion, so let's duplicate the parser
pTOP_STMT = pSTMT.copy()
pTOP_STMT.setParseAction(lambda result: {"result":"statement",
"stmt":result[0]})
pTOP_DECL = pDECL.copy()
pTOP_DECL.setParseAction(lambda result: {"result":"declaration",
"decl":result[0]})
pABSTRACT = "#abs" + pSTMT
pABSTRACT.setParseAction(lambda result: {"result":"abstract",
"stmt":result[1]})
pQUIT = Keyword("#quit")
pQUIT.setParseAction(lambda result: {"result":"quit"})
pTOP = ZeroOrMore(pTOP_DECL) + ZeroOrMore(pTOP_STMT)
return pTOP.parseString(input)
def reinit_exprs(self):
"""Combines all expressions into a single expression which can be used to match commands."""
command = reduce(lambda acc, e: acc | e[1], self.commands, NoMatch())
self.dm_expr = self.dm_expr_head + command
self.expr = self.expr_head + command
def evaluator(variables, functions, string, cs=False):
'''
Evaluate an expression. Variables are passed as a dictionary
from string to value. Unary functions are passed as a dictionary
from string to function. Variables must be floats.
cs: Case sensitive
TODO: Fix it so we can pass integers and complex numbers in variables dict
'''
# log.debug("variables: {0}".format(variables))
# log.debug("functions: {0}".format(functions))
# log.debug("string: {0}".format(string))
def lower_dict(d):
return dict([(k.lower(), d[k]) for k in d])
all_variables = copy.copy(default_variables)
all_functions = copy.copy(default_functions)
if not cs:
all_variables = lower_dict(all_variables)
all_functions = lower_dict(all_functions)
all_variables.update(variables)
all_functions.update(functions)
if not cs:
string_cs = string.lower()
all_functions = lower_dict(all_functions)
all_variables = lower_dict(all_variables)
CasedLiteral = CaselessLiteral
else:
string_cs = string
CasedLiteral = Literal
check_variables(string_cs, set(
all_variables.keys() + all_functions.keys()))
if string.strip() == "":
return float('nan')
ops = {"^": operator.pow,
"*": operator.mul,
"/": operator.truediv,
"+": operator.add,
"-": operator.sub,
}
# We eliminated extreme ones, since they're rarely used, and potentially
# confusing. They may also conflict with variables if we ever allow e.g.
# 5R instead of 5*R
suffixes = {'%': 0.01, 'k': 1e3, 'M': 1e6, 'G': 1e9,
'T': 1e12, # 'P':1e15,'E':1e18,'Z':1e21,'Y':1e24,
'c': 1e-2, 'm': 1e-3, 'u': 1e-6,
'n': 1e-9, 'p': 1e-12} # ,'f':1e-15,'a':1e-18,'z':1e-21,'y':1e-24}
def super_float(text):
''' Like float, but with si extensions. 1k goes to 1000'''
if text[-1] in suffixes:
return float(text[:-1]) * suffixes[text[-1]]
else:
return float(text)
def number_parse_action(x): # [ '7' ] -> [ 7 ]
return [super_float("".join(x))]
def exp_parse_action(x): # [ 2 ^ 3 ^ 2 ] -> 512
x = [e for e in x if isinstance(e, numbers.Number)] # Ignore ^
x.reverse()
x = reduce(lambda a, b: b ** a, x)
return x
def parallel(x): # Parallel resistors [ 1 2 ] => 2/3
# convert from pyparsing.ParseResults, which doesn't support '0 in x'
x = list(x)
if len(x) == 1:
return x[0]
if 0 in x:
return float('nan')
x = [1. / e for e in x if isinstance(e, numbers.Number)] # Ignore ||
return 1. / sum(x)
def sum_parse_action(x): # [ 1 + 2 - 3 ] -> 0
total = 0.0
op = ops['+']
for e in x:
if e in set('+-'):
op = ops[e]
else:
total = op(total, e)
return total
def prod_parse_action(x): # [ 1 * 2 / 3 ] => 0.66
prod = 1.0
op = ops['*']
for e in x:
if e in set('*/'):
op = ops[e]
else:
prod = op(prod, e)
return prod
def func_parse_action(x):
return [all_functions[x[0]](x[1])]
# SI suffixes and percent
number_suffix = reduce(lambda a, b: a | b, map(
Literal, suffixes.keys()), NoMatch())
(dot, minus, plus, times, div, lpar, rpar, exp) = map(Literal, ".-+*/()^")
number_part = Word(nums)
# 0.33 or 7 or .34 or 16.
inner_number = (number_part + Optional(
"." + Optional(number_part))) | ("." + number_part)
# 0.33k or -17
number = (Optional(minus | plus) + inner_number
+ Optional(CaselessLiteral("E") + Optional(
(plus | minus)) + number_part)
+ Optional(number_suffix))
number = number.setParseAction(number_parse_action) # Convert to number
# Predefine recursive variables
expr = Forward()
factor = Forward()
def sreduce(f, l):
''' Same as reduce, but handle len 1 and len 0 lists sensibly '''
if len(l) == 0:
return NoMatch()
if len(l) == 1:
return l[0]
return reduce(f, l)
# Handle variables passed in. E.g. if we have {'R':0.5}, we make the substitution.
# Special case for no variables because of how we understand PyParsing is
# put together
if len(all_variables) > 0:
# We sort the list so that var names (like "e2") match before
# mathematical constants (like "e"). This is kind of a hack.
all_variables_keys = sorted(
all_variables.keys(), key=len, reverse=True)
varnames = sreduce(lambda x, y: x | y, map(
lambda x: CasedLiteral(x), all_variables_keys))
varnames.setParseAction(lambda x: map(lambda y: all_variables[y], x))
else:
varnames = NoMatch()
# Same thing for functions.
if len(all_functions) > 0:
funcnames = sreduce(lambda x, y: x | y,
map(lambda x: CasedLiteral(x), all_functions.keys()))
function = funcnames + lpar.suppress() + expr + rpar.suppress()
function.setParseAction(func_parse_action)
else:
function = NoMatch()
atom = number | function | varnames | lpar + expr + rpar
factor << (atom + ZeroOrMore(
exp + atom)).setParseAction(exp_parse_action) # 7^6
paritem = factor + ZeroOrMore(Literal('||') + factor) # 5k || 4k
paritem = paritem.setParseAction(parallel)
term = paritem + ZeroOrMore((times | div) + paritem) # 7 * 5 / 4 - 3
term = term.setParseAction(prod_parse_action)
expr << Optional((plus | minus)) + term + ZeroOrMore(
(plus | minus) + term) # -5 + 4 - 3
expr = expr.setParseAction(sum_parse_action)
return (expr + stringEnd).parseString(string)[0]
def parse_imp(input):
# parse a string into an element of the abstract representation
# Grammar:
#
# <expr> ::= <integer>
# true
# false
# <identifier>
# ( if <expr> <expr> <expr> )
# ( function ( <name ... ) <expr> )
# ( <expr> <expr> ... )
#
# <decl> ::= var name = expr ;
#
# <stmt> ::= if <expr> <stmt> else <stmt>
# while <expr> <stmt>
# name <- <expr> ;
# print <expr> ;
# <block>
#
# <block> ::= { <decl> ... <stmt> ... }
#
# <toplevel> ::= <decl>
# <stmt>
#
idChars = alphas + "_+*-?!=<>+"
QUOTE = Literal('"')
INTERNAL_QUOTE = QUOTE.copy().leaveWhitespace()
pIDENTIFIER = Word(idChars, idChars + "0123456789")
#### NOTE THE DIFFERENCE
pIDENTIFIER.setParseAction(
lambda result: EPrimCall(oper_deref, [EId(result[0])]))
# A name is like an identifier but it does not return an EId...
pNAME = Word(idChars,
idChars + "0123456789") #| Keyword("&\"") | Keyword("&\'")
pNAMES = ZeroOrMore(pNAME)
pNAMES.setParseAction(lambda result: [result])
pINTEGER = Word("0123456789")
pINTEGER.setParseAction(lambda result: EValue(VInteger(int(result[0]))))
QUOTE = Literal("&\"") | Literal("&\'")
pSTRING = Literal('"') + ZeroOrMore(
Combine(Word(idChars + "0123456789'" + " ") | QUOTE)) + Literal('"')
pSTRING.setParseAction(lambda result: EValue(VString(str(result[1:-1]))))
pBOOLEAN = Keyword("true") | Keyword("false")
pBOOLEAN.setParseAction(
lambda result: EValue(VBoolean(result[0] == "true")))
pEXPR = Forward()
pEXPRS = ZeroOrMore(pEXPR)
pEXPRS.setParseAction(lambda result: [result])
pIF = "(" + Keyword("if") + pEXPR + pEXPR + pEXPR + ")"
pIF.setParseAction(lambda result: EIf(result[2], result[3], result[4]))
def mkFunBody(params, body):
bindings = [(p, ERefCell(EId(p))) for p in params]
return ELet(bindings, body)
def letToFun(result):
func = result[5]
binds = result[3]
params = []
vals = []
for p, v in binds:
params.append(p)
vals.append(v)
return ECall(EFunction(params, func), vals)
pFUN = "(" + Keyword("function") + "(" + pNAMES + ")" + pEXPR + ")"
pFUN.setParseAction(
lambda result: EFunction(result[3], mkFunBody(result[3], result[5])))
pBINDING = "(" + pNAME + pEXPR + ")"
pBINDING.setParseAction(lambda result: (result[1], result[2]))
pBINDINGS = OneOrMore(pBINDING)
pBINDINGS.setParseAction(lambda result: [result])
pLET = "(" + Keyword("let") + "(" + pBINDINGS + ")" + pEXPR + ")"
pLET.setParseAction(letToFun)
pCALL = "(" + pEXPR + pEXPRS + ")"
pCALL.setParseAction(lambda result: ECall(result[1], result[2]))
pARRAY = "(" + Keyword("new-array") + pEXPR + ")"
pARRAY.setParseAction(lambda result: EArray(result[2]))
pINDEX = Keyword("index") + pINTEGER
pCALL.setParseAction(lambda result: ECall(result[1], result[2]))
pWITH = "(" + Keyword("with") + pEXPR + pEXPR + ")"
pWITH.setParseAction(lambda result: EWithObj(result[2], result[3]))
pEXPR << (pINTEGER | pARRAY | pSTRING | pWITH | pBOOLEAN | pIDENTIFIER
| pIF | pLET | pFUN | pCALL)
pDECL_VAR = "var" + pNAME + "=" + pEXPR + ";"
pDECL_VAR.setParseAction(lambda result: (result[1], result[3]))
pSTMT = Forward()
pDECL_PROCEDURE = "procedure" + pNAME + "(" + pNAMES + ")" + pSTMT
pDECL_PROCEDURE.setParseAction(lambda result: (result[
1], EProcedure(result[3], mkFunBody(result[3], result[5]))))
# hack to get pDECL to match only PDECL_VAR (but still leave room
# to add to pDECL later)
pDECL = (pDECL_VAR | pDECL_PROCEDURE | NoMatch() | ";")
pDECLS = ZeroOrMore(pDECL)
pDECLS.setParseAction(lambda result: [result])
pSTMT_IF_1 = "if" + pEXPR + pSTMT + "else" + pSTMT
pSTMT_IF_1.setParseAction(
lambda result: EIf(result[1], result[2], result[4]))
pSTMT_IF_2 = "if" + pEXPR + pSTMT
pSTMT_IF_2.setParseAction(
lambda result: EIf(result[1], result[2], EValue(VBoolean(True))))
pSTMT_WHILE = "while" + pEXPR + pSTMT
pSTMT_WHILE.setParseAction(lambda result: EWhile(result[1], result[2]))
pSTMT_FOR = "for" + pDECLS + pEXPR + ";" + pSTMT + pSTMT
pSTMT_FOR.setParseAction(
lambda result: EFor(result[1], result[2], result[4], result[5]))
pSTMT_PRINT = "print" + pEXPR + ";"
pSTMT_PRINT.setParseAction(
lambda result: EPrimCall(oper_print, [result[1]]))
pSTMT_UPDATE_ARR = pNAME + "[" + pINTEGER + "]" + "<-" + pEXPR + ";"
pSTMT_UPDATE_ARR.setParseAction(lambda result: EPrimCall(
oper_update_arr, [EId(result[0]), result[2], result[5]]))
pSTMT_UPDATE = pNAME + "<-" + pEXPR + ";"
pSTMT_UPDATE.setParseAction(
lambda result: EPrimCall(oper_update, [EId(result[0]), result[2]]))
pSTMT_PROCEDURE = pEXPR + "(" + pEXPRS + ")" + ";"
pSTMT_PROCEDURE.setParseAction(lambda result: ECall(result[0], result[2]))
pSTMTS = ZeroOrMore(pSTMT)
pSTMTS.setParseAction(lambda result: [result])
def mkBlock(decls, stmts):
bindings = [(n, ERefCell(expr)) for (n, expr) in decls]
return ELet(bindings, EDo(stmts))
pSTMT_BLOCK = "{" + pDECLS + pSTMTS + "}"
pSTMT_BLOCK.setParseAction(lambda result: mkBlock(result[1], result[2]))
pSTMT << (pSTMT_IF_1 | pSTMT_IF_2 | pWITH | pSTMT_WHILE | pSTMT_FOR
| pSTMT_PRINT | pSTMT_UPDATE_ARR | pSTMT_UPDATE | pSTMT_PROCEDURE
| pSTMT_BLOCK)
# can't attach a parse action to pSTMT because of recursion, so let's duplicate the parser
pTOP_STMT = pSTMT.copy()
pTOP_STMT.setParseAction(lambda result: {
"result": "statement",
"stmt": result[0]
})
pTOP_DECL = pDECL.copy()
pTOP_DECL.setParseAction(lambda result: {
"result": "declaration",
"decl": result[0]
})
pABSTRACT = "#abs" + pSTMT
pABSTRACT.setParseAction(lambda result: {
"result": "abstract",
"stmt": result[1]
})
pQUIT = Keyword("#quit")
pQUIT.setParseAction(lambda result: {"result": "quit"})
pTOP = (pQUIT | pABSTRACT | pTOP_DECL | pTOP_STMT)
result = pTOP.parseString(input)[0]
return result # the first element of the result is the expression
def create_parser(regexes,
pattern_matchers,
range_fillers,
quote_pairs=[('\'', '\''), ('"', '"')],
delimiters=[','],
require_quotes=False,
require_delimiter=False,
allow_empty=True):
if isinstance(regexes, string_types) or isinstance(regexes,
re._pattern_type):
regexes = [regexes]
pattern_matchers = [pattern_matchers]
range_fillers = [range_fillers]
assert len(regexes) == len(pattern_matchers)
assert len(regexes) == len(range_fillers)
code_patterns = list(
starmap(
lambda regex, pattern_matcher: Regex(regex).setParseAction(
lambda s, loc, toks: frozenset(pattern_matcher(toks[0]))),
zip(regexes, pattern_matchers)))
if require_quotes:
quoted_code_patterns = [NoMatch() for _ in code_patterns]
else:
quoted_code_patterns = code_patterns
for opener, closer in quote_pairs:
quoted_code_patterns = list(
starmap(
lambda quoted_code_pattern, code_pattern: quoted_code_pattern |
(Literal(opener).suppress() + code_pattern + Literal(closer).
suppress()), zip(quoted_code_patterns, code_patterns)))
code_ranges = map(
lambda quoted_code_pattern: quoted_code_pattern + Literal('-').
suppress() + quoted_code_pattern, quoted_code_patterns)
code_ranges = list(
starmap(
lambda code_range, range_filler: code_range.
setParseAction(lambda s, loc, toks: frozenset(
range_filler(toks[0], toks[1]))),
zip(code_ranges, range_fillers)))
quoted_code_ranges = [NoMatch() for _ in code_ranges]
for opener, closer in quote_pairs:
quoted_code_ranges = list(
starmap(
lambda quoted_code_range, code_pattern: quoted_code_range |
(Literal(opener).suppress() + code_pattern + Literal('-').
suppress() + code_pattern + Literal(closer).suppress()),
zip(quoted_code_ranges, code_patterns)))
quoted_code_ranges = list(
starmap(
lambda quoted_code_range, range_filler: quoted_code_range.
setParseAction(lambda s, loc, toks: frozenset(
range_filler(toks[0], toks[1]))),
zip(quoted_code_ranges, range_fillers)))
any_code_ranges = list(starmap(or_, zip(quoted_code_ranges, code_ranges)))
quoted_code_pattern = reduce(xor, quoted_code_patterns)
any_code_range = reduce(xor, any_code_ranges)
any_delim = reduce(xor, map(Literal, delimiters))
if allow_empty:
any_delim = OneOrMore(any_delim)
code_list_continuation = any_delim.suppress() + (any_code_range
| quoted_code_pattern)
if not require_delimiter:
code_list_continuation |= White().suppress() + (any_code_range
| quoted_code_pattern)
code_list = (any_code_range | quoted_code_pattern) + ZeroOrMore(
code_list_continuation) + Optional(
reduce(or_, map(Literal, delimiters))).suppress() + StringEnd()
return code_list
def parse_imp(input):
# parse a string into an element of the abstract representation
# Grammar:
#
# <expr> ::= <integer>
# true
# false
# <identifier>
# ( if <expr> <expr> <expr> )
# ( function ( <name ... ) <expr> )
# ( <expr> <expr> ... )
#
# <decl> ::= var name = expr ;
#
# <stmt> ::= if <expr> <stmt> else <stmt>
# while <expr> <stmt>
# name <- <expr> ;
# print <expr> ;
# <expr> ;
# <block>
#
# <block> ::= { <decl> ... <stmt> ... }
#
# <toplevel> ::= <decl>
# <stmt>
#
idChars = alphas + "_+*-?!=<>"
pIDENTIFIER = Word(idChars, idChars + "0123456789")
#### NOTE THE DIFFERENCE
pIDENTIFIER.setParseAction(
lambda result: EPrimCall(oper_deref, [EId(result[0])]))
# A name is like an identifier but it does not return an EId...
pNAME = Word(idChars, idChars + "0123456789")
pNAMES = ZeroOrMore(pNAME)
pNAMES.setParseAction(lambda result: [result])
pINTEGER = Word("0123456789")
pINTEGER.setParseAction(lambda result: EValue(VInteger(int(result[0]))))
pBOOLEAN = Keyword("true") | Keyword("false")
pBOOLEAN.setParseAction(
lambda result: EValue(VBoolean(result[0] == "true")))
pEXPR = Forward()
pEXPRS = ZeroOrMore(pEXPR)
pEXPRS.setParseAction(lambda result: [result])
pIF = "(" + Keyword("if") + pEXPR + pEXPR + pEXPR + ")"
pIF.setParseAction(lambda result: EIf(result[2], result[3], result[4]))
def mkFunBody(params, body):
bindings = [(p, ERefCell(EId(p))) for p in params]
return ELet(bindings, body)
pFUN = "(" + Keyword("function") + "(" + pNAMES + ")" + pEXPR + ")"
pFUN.setParseAction(
lambda result: EFunction(result[3], mkFunBody(result[3], result[5])))
pCALL = "(" + pEXPR + pEXPRS + ")"
pCALL.setParseAction(lambda result: ECall(result[1], result[2]))
pEXPR << (pINTEGER | pBOOLEAN | pIDENTIFIER | pIF | pFUN | pCALL)
pDECL_VAR = "var" + pNAME + "=" + pEXPR + ";"
pDECL_VAR.setParseAction(lambda result: (result[1], result[3]))
# hack to get pDECL to match only PDECL_VAR (but still leave room
# to add to pDECL later)
pDECL = (pDECL_VAR | NoMatch())
pDECLS = ZeroOrMore(pDECL)
pDECLS.setParseAction(lambda result: [result])
pSTMT = Forward()
pSTMT_IF_1 = "if" + pEXPR + pSTMT + "else" + pSTMT
pSTMT_IF_1.setParseAction(
lambda result: EIf(result[1], result[2], result[4]))
pSTMT_IF_2 = "if" + pEXPR + pSTMT
pSTMT_IF_2.setParseAction(
lambda result: EIf(result[1], result[2], EValue(VBoolean(True))))
pSTMT_WHILE = "while" + pEXPR + pSTMT
pSTMT_WHILE.setParseAction(lambda result: EWhile(result[1], result[2]))
pSTMT_PRINT = "print" + pEXPR + ";"
pSTMT_PRINT.setParseAction(
lambda result: EPrimCall(oper_print, [result[1]]))
pSTMT_UPDATE = pNAME + "<-" + pEXPR + ";"
pSTMT_UPDATE.setParseAction(
lambda result: EPrimCall(oper_update, [EId(result[0]), result[2]]))
pSTMT_EXPR = pEXPR + ";"
pSTMT_EXPR.setParseAction(lambda result: result[0])
pSTMTS = ZeroOrMore(pSTMT)
pSTMTS.setParseAction(lambda result: [result])
def mkBlock(decls, stmts):
bindings = [(n, ERefCell(expr)) for (n, expr) in decls]
return ELet(bindings, EDo(stmts))
pSTMT_BLOCK = "{" + pDECLS + pSTMTS + "}"
pSTMT_BLOCK.setParseAction(lambda result: mkBlock(result[1], result[2]))
pSTMT << (pSTMT_IF_1 | pSTMT_IF_2 | pSTMT_WHILE | pSTMT_PRINT
| pSTMT_UPDATE | pSTMT_EXPR | pSTMT_BLOCK)
# can't attach a parse action to pSTMT because of recursion, so let's duplicate the parser
pTOP_STMT = pSTMT.copy()
pTOP_STMT.setParseAction(lambda result: {
"result": "statement",
"stmt": result[0]
})
pTOP_DECL = pDECL.copy()
pTOP_DECL.setParseAction(lambda result: {
"result": "declaration",
"decl": result[0]
})
pABSTRACT = "#abs" + pSTMT
pABSTRACT.setParseAction(lambda result: {
"result": "abstract",
"stmt": result[1]
})
pQUIT = Keyword("#quit")
pQUIT.setParseAction(lambda result: {"result": "quit"})
pTOP = (pQUIT | pABSTRACT | pTOP_DECL | pTOP_STMT)
result = pTOP.parseString(input)[0]
return result # the first element of the result is the expression