mirror of
https://github.com/CHOMPStation2/CHOMPStation2.git
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Moar whitespace normalization [MDB IGNORE] (#7750)
Co-authored-by: Raeschen <rycoop29@gmail.com>
This commit is contained in:
Drathek
GitHub
@@ -1,310 +1,310 @@
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/*
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File: Expressions
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Procedures for parsing expressions.
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*/
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/*
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Macros: Expression Macros
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OPERATOR - A value indicating the parser currently expects a binary operator.
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VALUE - A value indicating the parser currently expects a value.
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SHIFT - Tells the parser to push the current operator onto the stack.
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REDUCE - Tells the parser to reduce the stack.
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*/
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#define OPERATOR 1
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#define VALUE 2
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#define SHIFT 0
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#define REDUCE 1
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/*
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Class: nS_Parser
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*/
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/n_Parser/nS_Parser
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/*
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Var: expecting
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A variable which keeps track of whether an operator or value is expected. It should be either <OPERATOR> or <VALUE>. See <ParseExpression()>
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for more information.
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*/
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var/expecting=VALUE
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/*
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Proc: Precedence
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Compares two operators, decides which is higher in the order of operations, and returns <SHIFT> or <REDUCE>.
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*/
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/n_Parser/nS_Parser/proc/Precedence(node/expression/op/top, node/expression/op/input)
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if(istype(top))
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top=top.precedence
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if(istype(input))
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input=input:precedence
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if(top>=input)
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return REDUCE
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return SHIFT
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/*
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Proc: GetExpression
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Takes a token expected to represent a value and returns an <expression> node.
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*/
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/n_Parser/nS_Parser/proc/GetExpression(token/T)
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if(!T) return
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if(istype(T, /node/expression))
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return T
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switch(T.type)
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if(/token/word)
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return new/node/expression/value/variable(T.value)
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if(/token/accessor)
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var/token/accessor/A=T
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var/node/expression/value/variable/E//=new(A.member)
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var/stack/S=new()
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while(istype(A.object, /token/accessor))
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S.Push(A)
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A=A.object
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ASSERT(istext(A.object))
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while(A)
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var/node/expression/value/variable/V=new()
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V.id=new(A.member)
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if(E)
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V.object=E
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else
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V.object=new/node/identifier(A.object)
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E=V
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A=S.Pop()
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return E
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if(/token/number, /token/string)
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return new/node/expression/value/literal(T.value)
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/*
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Proc: GetOperator
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Gets a path related to a token or string and returns an instance of the given type. This is used to get an instance of either a binary or unary
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operator from a token.
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Parameters:
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O - The input value. If this is a token, O is reset to the token's value.
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When O is a string and is in L, its associated value is used as the path to instantiate.
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type - The desired type of the returned object.
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L - The list in which to search for O.
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See Also:
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- <GetBinaryOperator()>
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- <GetUnaryOperator()>
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*/
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/n_Parser/nS_Parser/proc/GetOperator(O, type=/node/expression/op, L[])
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if(istype(O, type)) return O //O is already the desired type
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if(istype(O, /token)) O=O:value //sets O to text
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if(istext(O)) //sets O to path
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if(L.Find(O)) O=L[O]
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else return null
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if(ispath(O))O=new O //catches path from last check
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else return null //Unknown type
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return O
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/*
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Proc: GetBinaryOperator
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Uses <GetOperator()> to search for an instance of a binary operator type with which the given string is associated. For example, if
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O is set to "+", an <Add> node is returned.
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See Also:
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- <GetOperator()>
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- <GetUnaryOperator()>
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*/
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/n_Parser/nS_Parser/proc/GetBinaryOperator(O)
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return GetOperator(O, /node/expression/op/binary, options.binary_operators)
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/*
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Proc: GetUnaryOperator
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Uses <GetOperator()> to search for an instance of a unary operator type with which the given string is associated. For example, if
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O is set to "!", a <LogicalNot> node is returned.
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See Also:
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- <GetOperator()>
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- <GetBinaryOperator()>
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*/
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/n_Parser/nS_Parser/proc/GetUnaryOperator(O)
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return GetOperator(O, /node/expression/op/unary, options.unary_operators)
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/*
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Proc: Reduce
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Takes the operator on top of the opr stack and assigns its operand(s). Then this proc pushes the value of that operation to the top
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of the val stack.
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*/
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/n_Parser/nS_Parser/proc/Reduce(stack/opr, stack/val)
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var/node/expression/op/O=opr.Pop()
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if(!O) return
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if(!istype(O))
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errors+=new/scriptError("Error reducing expression - invalid operator.")
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return
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//Take O and assign its operands, popping one or two values from the val stack
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//depending on whether O is a binary or unary operator.
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if(istype(O, /node/expression/op/binary))
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var/node/expression/op/binary/B=O
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B.exp2=val.Pop()
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B.exp =val.Pop()
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val.Push(B)
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else
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O.exp=val.Pop()
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val.Push(O)
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/*
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Proc: EndOfExpression
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Returns true if the current token represents the end of an expression.
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Parameters:
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end - A list of values to compare the current token to.
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*/
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/n_Parser/nS_Parser/proc/EndOfExpression(end[])
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if(!curToken)
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return 1
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if(istype(curToken, /token/symbol) && end.Find(curToken.value))
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return 1
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if(istype(curToken, /token/end) && end.Find(/token/end))
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return 1
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return 0
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/*
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Proc: ParseExpression
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Uses the Shunting-yard algorithm to parse expressions.
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Notes:
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- When an opening parenthesis is found, then <ParseParenExpression()> is called to handle it.
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- The <expecting> variable helps distinguish unary operators from binary operators (for cases like the - operator, which can be either).
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Articles:
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- <http://epaperpress.com/oper/>
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- <http://en.wikipedia.org/wiki/Shunting-yard_algorithm>
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See Also:
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- <ParseFunctionExpression()>
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- <ParseParenExpression()>
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- <ParseParamExpression()>
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*/
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/n_Parser/nS_Parser/proc/ParseExpression(list/end=list(/token/end), list/ErrChars=list("{", "}"))
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var/stack/opr=new
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var/stack/val=new
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src.expecting=VALUE
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while(TRUE)
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if(EndOfExpression(end))
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break
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if(istype(curToken, /token/symbol) && ErrChars.Find(curToken.value))
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errors+=new/scriptError/BadToken(curToken)
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break
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if(index>tokens.len) //End of File
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errors+=new/scriptError/EndOfFile()
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break
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var/token/ntok
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if(index+1<=tokens.len)
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ntok=tokens[index+1]
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if(istype(curToken, /token/symbol) && curToken.value=="(") //Parse parentheses expression
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if(expecting!=VALUE)
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errors+=new/scriptError/ExpectedToken("operator", curToken)
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NextToken()
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continue
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val.Push(ParseParenExpression())
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else if(istype(curToken, /token/symbol)) //Operator found.
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var/node/expression/op/curOperator //Figure out whether it is unary or binary and get a new instance.
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if(src.expecting==OPERATOR)
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curOperator=GetBinaryOperator(curToken)
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if(!curOperator)
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errors+=new/scriptError/ExpectedToken("operator", curToken)
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NextToken()
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continue
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else
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curOperator=GetUnaryOperator(curToken)
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if(!curOperator) //given symbol isn't a unary operator
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errors+=new/scriptError/ExpectedToken("expression", curToken)
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NextToken()
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continue
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if(opr.Top() && Precedence(opr.Top(), curOperator)==REDUCE) //Check order of operations and reduce if necessary
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Reduce(opr, val)
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continue
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opr.Push(curOperator)
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src.expecting=VALUE
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else if(ntok && ntok.value=="(" && istype(ntok, /token/symbol)\
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&& istype(curToken, /token/word)) //Parse function call
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var/token/preToken=curToken
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var/old_expect=src.expecting
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var/fex=ParseFunctionExpression()
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if(old_expect!=VALUE)
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errors+=new/scriptError/ExpectedToken("operator", preToken)
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NextToken()
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continue
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val.Push(fex)
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else if(istype(curToken, /token/keyword)) //inline keywords
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var/n_Keyword/kw=options.keywords[curToken.value]
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kw=new kw(inline=1)
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if(kw)
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if(!kw.Parse(src))
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return
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else
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errors+=new/scriptError/BadToken(curToken)
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else if(istype(curToken, /token/end)) //semicolon found where it wasn't expected
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errors+=new/scriptError/BadToken(curToken)
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NextToken()
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continue
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else
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if(expecting!=VALUE)
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errors+=new/scriptError/ExpectedToken("operator", curToken)
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NextToken()
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continue
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val.Push(GetExpression(curToken))
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src.expecting=OPERATOR
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NextToken()
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while(opr.Top()) Reduce(opr, val) //Reduce the value stack completely
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.=val.Pop() //Return what should be the last value on the stack
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if(val.Top()) //
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var/node/N=val.Pop()
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errors+=new/scriptError("Error parsing expression. Unexpected value left on stack: [N.ToString()].")
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return null
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/*
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Proc: ParseFunctionExpression
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Parses a function call inside of an expression.
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See Also:
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- <ParseExpression()>
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*/
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/n_Parser/nS_Parser/proc/ParseFunctionExpression()
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var/node/expression/FunctionCall/exp=new
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exp.func_name=curToken.value
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NextToken() //skip function name
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NextToken() //skip open parenthesis, already found
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var/loops = 0
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while(TRUE)
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loops++
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if(loops>=1000)
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CRASH("Something TERRIBLE has gone wrong in ParseFunctionExpression ;__;")
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if(istype(curToken, /token/symbol) && curToken.value==")")
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return exp
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exp.parameters+=ParseParamExpression()
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if(curToken.value==","&&istype(curToken, /token/symbol))NextToken() //skip comma
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if(istype(curToken, /token/end)) //Prevents infinite loop...
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errors+=new/scriptError/ExpectedToken(")")
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return exp
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/*
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Proc: ParseParenExpression
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Parses an expression that ends with a close parenthesis. This is used for parsing expressions inside of parentheses.
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See Also:
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- <ParseExpression()>
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*/
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/n_Parser/nS_Parser/proc/ParseParenExpression()
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if(!CheckToken("(", /token/symbol))
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return
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return new/node/expression/op/unary/group(ParseExpression(list(")")))
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/*
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Proc: ParseParamExpression
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Parses an expression that ends with either a comma or close parenthesis. This is used for parsing the parameters passed to a function call.
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See Also:
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- <ParseExpression()>
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*/
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/n_Parser/nS_Parser/proc/ParseParamExpression()
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return ParseExpression(list(",", ")"))
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/*
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File: Expressions
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Procedures for parsing expressions.
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*/
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/*
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Macros: Expression Macros
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OPERATOR - A value indicating the parser currently expects a binary operator.
|
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VALUE - A value indicating the parser currently expects a value.
|
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SHIFT - Tells the parser to push the current operator onto the stack.
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REDUCE - Tells the parser to reduce the stack.
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*/
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#define OPERATOR 1
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#define VALUE 2
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#define SHIFT 0
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#define REDUCE 1
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/*
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Class: nS_Parser
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*/
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/n_Parser/nS_Parser
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/*
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Var: expecting
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A variable which keeps track of whether an operator or value is expected. It should be either <OPERATOR> or <VALUE>. See <ParseExpression()>
|
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for more information.
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*/
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var/expecting=VALUE
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/*
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Proc: Precedence
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Compares two operators, decides which is higher in the order of operations, and returns <SHIFT> or <REDUCE>.
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*/
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/n_Parser/nS_Parser/proc/Precedence(node/expression/op/top, node/expression/op/input)
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if(istype(top))
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top=top.precedence
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if(istype(input))
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input=input:precedence
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if(top>=input)
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return REDUCE
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return SHIFT
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/*
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Proc: GetExpression
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Takes a token expected to represent a value and returns an <expression> node.
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*/
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/n_Parser/nS_Parser/proc/GetExpression(token/T)
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if(!T) return
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if(istype(T, /node/expression))
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return T
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switch(T.type)
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if(/token/word)
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return new/node/expression/value/variable(T.value)
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if(/token/accessor)
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var/token/accessor/A=T
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var/node/expression/value/variable/E//=new(A.member)
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var/stack/S=new()
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while(istype(A.object, /token/accessor))
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S.Push(A)
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A=A.object
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ASSERT(istext(A.object))
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while(A)
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var/node/expression/value/variable/V=new()
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V.id=new(A.member)
|
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if(E)
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V.object=E
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else
|
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V.object=new/node/identifier(A.object)
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E=V
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A=S.Pop()
|
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return E
|
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|
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if(/token/number, /token/string)
|
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return new/node/expression/value/literal(T.value)
|
||||
|
||||
/*
|
||||
Proc: GetOperator
|
||||
Gets a path related to a token or string and returns an instance of the given type. This is used to get an instance of either a binary or unary
|
||||
operator from a token.
|
||||
|
||||
Parameters:
|
||||
O - The input value. If this is a token, O is reset to the token's value.
|
||||
When O is a string and is in L, its associated value is used as the path to instantiate.
|
||||
type - The desired type of the returned object.
|
||||
L - The list in which to search for O.
|
||||
|
||||
See Also:
|
||||
- <GetBinaryOperator()>
|
||||
- <GetUnaryOperator()>
|
||||
*/
|
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/n_Parser/nS_Parser/proc/GetOperator(O, type=/node/expression/op, L[])
|
||||
if(istype(O, type)) return O //O is already the desired type
|
||||
if(istype(O, /token)) O=O:value //sets O to text
|
||||
if(istext(O)) //sets O to path
|
||||
if(L.Find(O)) O=L[O]
|
||||
else return null
|
||||
if(ispath(O))O=new O //catches path from last check
|
||||
else return null //Unknown type
|
||||
return O
|
||||
|
||||
/*
|
||||
Proc: GetBinaryOperator
|
||||
Uses <GetOperator()> to search for an instance of a binary operator type with which the given string is associated. For example, if
|
||||
O is set to "+", an <Add> node is returned.
|
||||
|
||||
See Also:
|
||||
- <GetOperator()>
|
||||
- <GetUnaryOperator()>
|
||||
*/
|
||||
/n_Parser/nS_Parser/proc/GetBinaryOperator(O)
|
||||
return GetOperator(O, /node/expression/op/binary, options.binary_operators)
|
||||
|
||||
/*
|
||||
Proc: GetUnaryOperator
|
||||
Uses <GetOperator()> to search for an instance of a unary operator type with which the given string is associated. For example, if
|
||||
O is set to "!", a <LogicalNot> node is returned.
|
||||
|
||||
See Also:
|
||||
- <GetOperator()>
|
||||
- <GetBinaryOperator()>
|
||||
*/
|
||||
/n_Parser/nS_Parser/proc/GetUnaryOperator(O)
|
||||
return GetOperator(O, /node/expression/op/unary, options.unary_operators)
|
||||
|
||||
/*
|
||||
Proc: Reduce
|
||||
Takes the operator on top of the opr stack and assigns its operand(s). Then this proc pushes the value of that operation to the top
|
||||
of the val stack.
|
||||
*/
|
||||
/n_Parser/nS_Parser/proc/Reduce(stack/opr, stack/val)
|
||||
var/node/expression/op/O=opr.Pop()
|
||||
if(!O) return
|
||||
if(!istype(O))
|
||||
errors+=new/scriptError("Error reducing expression - invalid operator.")
|
||||
return
|
||||
//Take O and assign its operands, popping one or two values from the val stack
|
||||
//depending on whether O is a binary or unary operator.
|
||||
if(istype(O, /node/expression/op/binary))
|
||||
var/node/expression/op/binary/B=O
|
||||
B.exp2=val.Pop()
|
||||
B.exp =val.Pop()
|
||||
val.Push(B)
|
||||
else
|
||||
O.exp=val.Pop()
|
||||
val.Push(O)
|
||||
|
||||
/*
|
||||
Proc: EndOfExpression
|
||||
Returns true if the current token represents the end of an expression.
|
||||
|
||||
Parameters:
|
||||
end - A list of values to compare the current token to.
|
||||
*/
|
||||
/n_Parser/nS_Parser/proc/EndOfExpression(end[])
|
||||
if(!curToken)
|
||||
return 1
|
||||
if(istype(curToken, /token/symbol) && end.Find(curToken.value))
|
||||
return 1
|
||||
if(istype(curToken, /token/end) && end.Find(/token/end))
|
||||
return 1
|
||||
return 0
|
||||
|
||||
/*
|
||||
Proc: ParseExpression
|
||||
Uses the Shunting-yard algorithm to parse expressions.
|
||||
|
||||
Notes:
|
||||
- When an opening parenthesis is found, then <ParseParenExpression()> is called to handle it.
|
||||
- The <expecting> variable helps distinguish unary operators from binary operators (for cases like the - operator, which can be either).
|
||||
|
||||
Articles:
|
||||
- <http://epaperpress.com/oper/>
|
||||
- <http://en.wikipedia.org/wiki/Shunting-yard_algorithm>
|
||||
|
||||
See Also:
|
||||
- <ParseFunctionExpression()>
|
||||
- <ParseParenExpression()>
|
||||
- <ParseParamExpression()>
|
||||
*/
|
||||
/n_Parser/nS_Parser/proc/ParseExpression(list/end=list(/token/end), list/ErrChars=list("{", "}"))
|
||||
var/stack/opr=new
|
||||
var/stack/val=new
|
||||
src.expecting=VALUE
|
||||
while(TRUE)
|
||||
if(EndOfExpression(end))
|
||||
break
|
||||
if(istype(curToken, /token/symbol) && ErrChars.Find(curToken.value))
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
break
|
||||
|
||||
|
||||
if(index>tokens.len) //End of File
|
||||
errors+=new/scriptError/EndOfFile()
|
||||
break
|
||||
var/token/ntok
|
||||
if(index+1<=tokens.len)
|
||||
ntok=tokens[index+1]
|
||||
|
||||
if(istype(curToken, /token/symbol) && curToken.value=="(") //Parse parentheses expression
|
||||
if(expecting!=VALUE)
|
||||
errors+=new/scriptError/ExpectedToken("operator", curToken)
|
||||
NextToken()
|
||||
continue
|
||||
val.Push(ParseParenExpression())
|
||||
else if(istype(curToken, /token/symbol)) //Operator found.
|
||||
var/node/expression/op/curOperator //Figure out whether it is unary or binary and get a new instance.
|
||||
if(src.expecting==OPERATOR)
|
||||
curOperator=GetBinaryOperator(curToken)
|
||||
if(!curOperator)
|
||||
errors+=new/scriptError/ExpectedToken("operator", curToken)
|
||||
NextToken()
|
||||
continue
|
||||
else
|
||||
curOperator=GetUnaryOperator(curToken)
|
||||
if(!curOperator) //given symbol isn't a unary operator
|
||||
errors+=new/scriptError/ExpectedToken("expression", curToken)
|
||||
NextToken()
|
||||
continue
|
||||
|
||||
if(opr.Top() && Precedence(opr.Top(), curOperator)==REDUCE) //Check order of operations and reduce if necessary
|
||||
Reduce(opr, val)
|
||||
continue
|
||||
opr.Push(curOperator)
|
||||
src.expecting=VALUE
|
||||
else if(ntok && ntok.value=="(" && istype(ntok, /token/symbol)\
|
||||
&& istype(curToken, /token/word)) //Parse function call
|
||||
var/token/preToken=curToken
|
||||
var/old_expect=src.expecting
|
||||
var/fex=ParseFunctionExpression()
|
||||
if(old_expect!=VALUE)
|
||||
errors+=new/scriptError/ExpectedToken("operator", preToken)
|
||||
NextToken()
|
||||
continue
|
||||
val.Push(fex)
|
||||
else if(istype(curToken, /token/keyword)) //inline keywords
|
||||
var/n_Keyword/kw=options.keywords[curToken.value]
|
||||
kw=new kw(inline=1)
|
||||
if(kw)
|
||||
if(!kw.Parse(src))
|
||||
return
|
||||
else
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
else if(istype(curToken, /token/end)) //semicolon found where it wasn't expected
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
NextToken()
|
||||
continue
|
||||
else
|
||||
if(expecting!=VALUE)
|
||||
errors+=new/scriptError/ExpectedToken("operator", curToken)
|
||||
NextToken()
|
||||
continue
|
||||
val.Push(GetExpression(curToken))
|
||||
src.expecting=OPERATOR
|
||||
NextToken()
|
||||
|
||||
while(opr.Top()) Reduce(opr, val) //Reduce the value stack completely
|
||||
.=val.Pop() //Return what should be the last value on the stack
|
||||
if(val.Top()) //
|
||||
var/node/N=val.Pop()
|
||||
errors+=new/scriptError("Error parsing expression. Unexpected value left on stack: [N.ToString()].")
|
||||
return null
|
||||
|
||||
/*
|
||||
Proc: ParseFunctionExpression
|
||||
Parses a function call inside of an expression.
|
||||
|
||||
See Also:
|
||||
- <ParseExpression()>
|
||||
*/
|
||||
/n_Parser/nS_Parser/proc/ParseFunctionExpression()
|
||||
var/node/expression/FunctionCall/exp=new
|
||||
exp.func_name=curToken.value
|
||||
NextToken() //skip function name
|
||||
NextToken() //skip open parenthesis, already found
|
||||
var/loops = 0
|
||||
|
||||
while(TRUE)
|
||||
loops++
|
||||
if(loops>=1000)
|
||||
CRASH("Something TERRIBLE has gone wrong in ParseFunctionExpression ;__;")
|
||||
|
||||
if(istype(curToken, /token/symbol) && curToken.value==")")
|
||||
return exp
|
||||
exp.parameters+=ParseParamExpression()
|
||||
if(curToken.value==","&&istype(curToken, /token/symbol))NextToken() //skip comma
|
||||
if(istype(curToken, /token/end)) //Prevents infinite loop...
|
||||
errors+=new/scriptError/ExpectedToken(")")
|
||||
return exp
|
||||
|
||||
/*
|
||||
Proc: ParseParenExpression
|
||||
Parses an expression that ends with a close parenthesis. This is used for parsing expressions inside of parentheses.
|
||||
|
||||
See Also:
|
||||
- <ParseExpression()>
|
||||
*/
|
||||
/n_Parser/nS_Parser/proc/ParseParenExpression()
|
||||
if(!CheckToken("(", /token/symbol))
|
||||
return
|
||||
return new/node/expression/op/unary/group(ParseExpression(list(")")))
|
||||
|
||||
/*
|
||||
Proc: ParseParamExpression
|
||||
Parses an expression that ends with either a comma or close parenthesis. This is used for parsing the parameters passed to a function call.
|
||||
|
||||
See Also:
|
||||
- <ParseExpression()>
|
||||
*/
|
||||
/n_Parser/nS_Parser/proc/ParseParamExpression()
|
||||
return ParseExpression(list(",", ")"))
|
||||
|
||||
@@ -1,158 +1,158 @@
|
||||
//This file was auto-corrected by findeclaration.exe on 25.5.2012 20:42:33
|
||||
|
||||
/*
|
||||
File: Keywords
|
||||
*/
|
||||
var/const/KW_FAIL = 0 //Fatal error; stop parsing entire script.
|
||||
var/const/KW_PASS = 1 //OK
|
||||
var/const/KW_ERR = 2 //Non-fatal error, keyword couldn't be handled properly. Ignore keyword but continue on.
|
||||
var/const/KW_WARN = 3 //Warning
|
||||
|
||||
/*
|
||||
var/const/Class: n_Keyword
|
||||
var/const/Represents a special statement in the code triggered by a keyword.
|
||||
*/
|
||||
|
||||
/*
|
||||
Var: inline
|
||||
1 if the keyword is in an expression (e.g. the new keyword in many languages), 0 otherwise (such as the if and else keywords).
|
||||
*/
|
||||
/n_Keyword
|
||||
var/inline
|
||||
/n_Keyword/New(inline=FALSE)
|
||||
src.inline=inline
|
||||
return ..()
|
||||
|
||||
/*
|
||||
Proc: Parse
|
||||
Called when the parser finds a keyword in the code.
|
||||
|
||||
Parameters:
|
||||
parser - The parser that created this object. You can use the parameter to manipulate the parser in order to add statements and blocks
|
||||
to its AST.
|
||||
*/
|
||||
/n_Keyword/proc/Parse(n_Parser/parser)
|
||||
|
||||
/*
|
||||
Class: nS_Keyword
|
||||
A keyword in n_Script. By default these include return, if, else, while, and def. To enable or disable a keyword, change the
|
||||
<nS_Options.keywords> list.
|
||||
|
||||
Behavior:
|
||||
When a parser is expecting a new statement, and a keyword listed in <nS_Options.keywords> is found, it will call the keyword's
|
||||
<n_Keyword.Parse()> proc.
|
||||
*/
|
||||
//
|
||||
/n_Keyword/nS_Keyword/New(inline=0)
|
||||
if(inline)
|
||||
qdel(src)
|
||||
|
||||
/n_Keyword/nS_Keyword/kwReturn/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
if(istype(parser.curBlock, /node/BlockDefinition/GlobalBlock))
|
||||
parser.errors+=new/scriptError/BadReturn(parser.curToken)
|
||||
. = KW_WARN
|
||||
var/node/statement/ReturnStatement/stmt=new
|
||||
parser.NextToken() //skip 'return' token
|
||||
stmt.value=parser.ParseExpression()
|
||||
parser.curBlock.statements+=stmt
|
||||
|
||||
/n_Keyword/nS_Keyword/kwIf/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
var/node/statement/IfStatement/stmt=new
|
||||
parser.NextToken() //skip 'if' token
|
||||
stmt.cond=parser.ParseParenExpression()
|
||||
if(!parser.CheckToken(")", /token/symbol))
|
||||
return KW_FAIL
|
||||
if(!parser.CheckToken("{", /token/symbol, skip=0)) //Token needs to be preserved for parse loop, so skip=0
|
||||
return KW_ERR
|
||||
parser.curBlock.statements+=stmt
|
||||
stmt.block=new
|
||||
parser.AddBlock(stmt.block)
|
||||
|
||||
/n_Keyword/nS_Keyword/kwElse/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
var/list/L=parser.curBlock.statements
|
||||
var/node/statement/IfStatement/stmt
|
||||
if(L&&L.len) stmt=L[L.len] //Get the last statement in the current block
|
||||
if(!stmt || !istype(stmt) || stmt.else_block) //Ensure that it is an if statement
|
||||
parser.errors+=new/scriptError/ExpectedToken("if statement",parser.curToken)
|
||||
return KW_FAIL
|
||||
parser.NextToken() //skip 'else' token
|
||||
if(!parser.CheckToken("{", /token/symbol, skip=0))
|
||||
return KW_ERR
|
||||
stmt.else_block=new()
|
||||
parser.AddBlock(stmt.else_block)
|
||||
|
||||
/n_Keyword/nS_Keyword/kwWhile/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
var/node/statement/WhileLoop/stmt=new
|
||||
parser.NextToken() //skip 'while' token
|
||||
stmt.cond=parser.ParseParenExpression()
|
||||
if(!parser.CheckToken(")", /token/symbol))
|
||||
return KW_FAIL
|
||||
if(!parser.CheckToken("{", /token/symbol, skip=0))
|
||||
return KW_ERR
|
||||
parser.curBlock.statements+=stmt
|
||||
stmt.block=new
|
||||
parser.AddBlock(stmt.block)
|
||||
|
||||
/n_Keyword/nS_Keyword/kwBreak/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
if(istype(parser.curBlock, /node/BlockDefinition/GlobalBlock))
|
||||
parser.errors+=new/scriptError/BadToken(parser.curToken)
|
||||
. = KW_WARN
|
||||
var/node/statement/BreakStatement/stmt=new
|
||||
parser.NextToken() //skip 'break' token
|
||||
parser.curBlock.statements+=stmt
|
||||
|
||||
/n_Keyword/nS_Keyword/kwContinue/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
if(istype(parser.curBlock, /node/BlockDefinition/GlobalBlock))
|
||||
parser.errors+=new/scriptError/BadToken(parser.curToken)
|
||||
. = KW_WARN
|
||||
var/node/statement/ContinueStatement/stmt=new
|
||||
parser.NextToken() //skip 'break' token
|
||||
parser.curBlock.statements+=stmt
|
||||
|
||||
/n_Keyword/nS_Keyword/kwDef/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
var/node/statement/FunctionDefinition/def=new
|
||||
parser.NextToken() //skip 'def' token
|
||||
if(!parser.options.IsValidID(parser.curToken.value))
|
||||
parser.errors+=new/scriptError/InvalidID(parser.curToken)
|
||||
return KW_FAIL
|
||||
def.func_name=parser.curToken.value
|
||||
parser.NextToken()
|
||||
if(!parser.CheckToken("(", /token/symbol))
|
||||
return KW_FAIL
|
||||
while(TRUE) //for now parameters can be separated by whitespace - they don't need a comma in between
|
||||
if(istype(parser.curToken, /token/symbol))
|
||||
switch(parser.curToken.value)
|
||||
if(",")
|
||||
parser.NextToken()
|
||||
if(")")
|
||||
break
|
||||
else
|
||||
parser.errors+=new/scriptError/BadToken(parser.curToken)
|
||||
return KW_ERR
|
||||
|
||||
else if(istype(parser.curToken, /token/word))
|
||||
def.parameters+=parser.curToken.value
|
||||
parser.NextToken()
|
||||
else
|
||||
parser.errors+=new/scriptError/InvalidID(parser.curToken)
|
||||
return KW_ERR
|
||||
if(!parser.CheckToken(")", /token/symbol))
|
||||
return KW_FAIL
|
||||
|
||||
if(istype(parser.curToken, /token/end)) //Function prototype
|
||||
parser.curBlock.statements+=def
|
||||
else if(parser.curToken.value=="{" && istype(parser.curToken, /token/symbol))
|
||||
def.block = new
|
||||
parser.curBlock.statements+=def
|
||||
parser.curBlock.functions[def.func_name]=def
|
||||
parser.AddBlock(def.block)
|
||||
else
|
||||
parser.errors+=new/scriptError/BadToken(parser.curToken)
|
||||
return KW_FAIL
|
||||
//This file was auto-corrected by findeclaration.exe on 25.5.2012 20:42:33
|
||||
|
||||
/*
|
||||
File: Keywords
|
||||
*/
|
||||
var/const/KW_FAIL = 0 //Fatal error; stop parsing entire script.
|
||||
var/const/KW_PASS = 1 //OK
|
||||
var/const/KW_ERR = 2 //Non-fatal error, keyword couldn't be handled properly. Ignore keyword but continue on.
|
||||
var/const/KW_WARN = 3 //Warning
|
||||
|
||||
/*
|
||||
var/const/Class: n_Keyword
|
||||
var/const/Represents a special statement in the code triggered by a keyword.
|
||||
*/
|
||||
|
||||
/*
|
||||
Var: inline
|
||||
1 if the keyword is in an expression (e.g. the new keyword in many languages), 0 otherwise (such as the if and else keywords).
|
||||
*/
|
||||
/n_Keyword
|
||||
var/inline
|
||||
/n_Keyword/New(inline=FALSE)
|
||||
src.inline=inline
|
||||
return ..()
|
||||
|
||||
/*
|
||||
Proc: Parse
|
||||
Called when the parser finds a keyword in the code.
|
||||
|
||||
Parameters:
|
||||
parser - The parser that created this object. You can use the parameter to manipulate the parser in order to add statements and blocks
|
||||
to its AST.
|
||||
*/
|
||||
/n_Keyword/proc/Parse(n_Parser/parser)
|
||||
|
||||
/*
|
||||
Class: nS_Keyword
|
||||
A keyword in n_Script. By default these include return, if, else, while, and def. To enable or disable a keyword, change the
|
||||
<nS_Options.keywords> list.
|
||||
|
||||
Behavior:
|
||||
When a parser is expecting a new statement, and a keyword listed in <nS_Options.keywords> is found, it will call the keyword's
|
||||
<n_Keyword.Parse()> proc.
|
||||
*/
|
||||
//
|
||||
/n_Keyword/nS_Keyword/New(inline=0)
|
||||
if(inline)
|
||||
qdel(src)
|
||||
|
||||
/n_Keyword/nS_Keyword/kwReturn/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
if(istype(parser.curBlock, /node/BlockDefinition/GlobalBlock))
|
||||
parser.errors+=new/scriptError/BadReturn(parser.curToken)
|
||||
. = KW_WARN
|
||||
var/node/statement/ReturnStatement/stmt=new
|
||||
parser.NextToken() //skip 'return' token
|
||||
stmt.value=parser.ParseExpression()
|
||||
parser.curBlock.statements+=stmt
|
||||
|
||||
/n_Keyword/nS_Keyword/kwIf/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
var/node/statement/IfStatement/stmt=new
|
||||
parser.NextToken() //skip 'if' token
|
||||
stmt.cond=parser.ParseParenExpression()
|
||||
if(!parser.CheckToken(")", /token/symbol))
|
||||
return KW_FAIL
|
||||
if(!parser.CheckToken("{", /token/symbol, skip=0)) //Token needs to be preserved for parse loop, so skip=0
|
||||
return KW_ERR
|
||||
parser.curBlock.statements+=stmt
|
||||
stmt.block=new
|
||||
parser.AddBlock(stmt.block)
|
||||
|
||||
/n_Keyword/nS_Keyword/kwElse/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
var/list/L=parser.curBlock.statements
|
||||
var/node/statement/IfStatement/stmt
|
||||
if(L&&L.len) stmt=L[L.len] //Get the last statement in the current block
|
||||
if(!stmt || !istype(stmt) || stmt.else_block) //Ensure that it is an if statement
|
||||
parser.errors+=new/scriptError/ExpectedToken("if statement",parser.curToken)
|
||||
return KW_FAIL
|
||||
parser.NextToken() //skip 'else' token
|
||||
if(!parser.CheckToken("{", /token/symbol, skip=0))
|
||||
return KW_ERR
|
||||
stmt.else_block=new()
|
||||
parser.AddBlock(stmt.else_block)
|
||||
|
||||
/n_Keyword/nS_Keyword/kwWhile/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
var/node/statement/WhileLoop/stmt=new
|
||||
parser.NextToken() //skip 'while' token
|
||||
stmt.cond=parser.ParseParenExpression()
|
||||
if(!parser.CheckToken(")", /token/symbol))
|
||||
return KW_FAIL
|
||||
if(!parser.CheckToken("{", /token/symbol, skip=0))
|
||||
return KW_ERR
|
||||
parser.curBlock.statements+=stmt
|
||||
stmt.block=new
|
||||
parser.AddBlock(stmt.block)
|
||||
|
||||
/n_Keyword/nS_Keyword/kwBreak/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
if(istype(parser.curBlock, /node/BlockDefinition/GlobalBlock))
|
||||
parser.errors+=new/scriptError/BadToken(parser.curToken)
|
||||
. = KW_WARN
|
||||
var/node/statement/BreakStatement/stmt=new
|
||||
parser.NextToken() //skip 'break' token
|
||||
parser.curBlock.statements+=stmt
|
||||
|
||||
/n_Keyword/nS_Keyword/kwContinue/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
if(istype(parser.curBlock, /node/BlockDefinition/GlobalBlock))
|
||||
parser.errors+=new/scriptError/BadToken(parser.curToken)
|
||||
. = KW_WARN
|
||||
var/node/statement/ContinueStatement/stmt=new
|
||||
parser.NextToken() //skip 'break' token
|
||||
parser.curBlock.statements+=stmt
|
||||
|
||||
/n_Keyword/nS_Keyword/kwDef/Parse(n_Parser/nS_Parser/parser)
|
||||
.=KW_PASS
|
||||
var/node/statement/FunctionDefinition/def=new
|
||||
parser.NextToken() //skip 'def' token
|
||||
if(!parser.options.IsValidID(parser.curToken.value))
|
||||
parser.errors+=new/scriptError/InvalidID(parser.curToken)
|
||||
return KW_FAIL
|
||||
def.func_name=parser.curToken.value
|
||||
parser.NextToken()
|
||||
if(!parser.CheckToken("(", /token/symbol))
|
||||
return KW_FAIL
|
||||
while(TRUE) //for now parameters can be separated by whitespace - they don't need a comma in between
|
||||
if(istype(parser.curToken, /token/symbol))
|
||||
switch(parser.curToken.value)
|
||||
if(",")
|
||||
parser.NextToken()
|
||||
if(")")
|
||||
break
|
||||
else
|
||||
parser.errors+=new/scriptError/BadToken(parser.curToken)
|
||||
return KW_ERR
|
||||
|
||||
else if(istype(parser.curToken, /token/word))
|
||||
def.parameters+=parser.curToken.value
|
||||
parser.NextToken()
|
||||
else
|
||||
parser.errors+=new/scriptError/InvalidID(parser.curToken)
|
||||
return KW_ERR
|
||||
if(!parser.CheckToken(")", /token/symbol))
|
||||
return KW_FAIL
|
||||
|
||||
if(istype(parser.curToken, /token/end)) //Function prototype
|
||||
parser.curBlock.statements+=def
|
||||
else if(parser.curToken.value=="{" && istype(parser.curToken, /token/symbol))
|
||||
def.block = new
|
||||
parser.curBlock.statements+=def
|
||||
parser.curBlock.functions[def.func_name]=def
|
||||
parser.AddBlock(def.block)
|
||||
else
|
||||
parser.errors+=new/scriptError/BadToken(parser.curToken)
|
||||
return KW_FAIL
|
||||
|
||||
@@ -1,182 +1,182 @@
|
||||
/*
|
||||
File: Parser
|
||||
*/
|
||||
/*
|
||||
Class: n_Parser
|
||||
An object that reads tokens and produces an AST (abstract syntax tree).
|
||||
*/
|
||||
/n_Parser
|
||||
var/index = 1
|
||||
/*
|
||||
Var: index
|
||||
The parser's current position in the token's list.
|
||||
*/
|
||||
/*
|
||||
Var: tokens
|
||||
A list of tokens in the source code generated by a scanner.
|
||||
*/
|
||||
var/list/tokens = new
|
||||
/*
|
||||
Var: errors
|
||||
A list of fatal errors found by the parser. If there are any items in this list, then it is not safe to run the returned AST.
|
||||
|
||||
See Also:
|
||||
- <scriptError>
|
||||
*/
|
||||
var/list/errors = new
|
||||
/*
|
||||
Var: warnings
|
||||
A list of non-fatal problems in the script.
|
||||
*/
|
||||
var/list/warnings = new
|
||||
/*
|
||||
Var: curToken
|
||||
The token at <index> in <tokens>.
|
||||
*/
|
||||
var/token/curToken
|
||||
var/stack/blocks=new
|
||||
var/node/BlockDefinition/GlobalBlock/global_block=new
|
||||
var/node/BlockDefinition/curBlock
|
||||
|
||||
/*
|
||||
Proc: Parse
|
||||
Reads the tokens and returns the AST's <GlobalBlock> node. Be sure to populate the tokens list before calling this procedure.
|
||||
*/
|
||||
/n_Parser/proc/Parse()
|
||||
|
||||
/*
|
||||
Proc: NextToken
|
||||
Sets <curToken> to the next token in the <tokens> list, or null if there are no more tokens.
|
||||
*/
|
||||
/n_Parser/proc/NextToken()
|
||||
if(index>=tokens.len)
|
||||
curToken=null
|
||||
else
|
||||
curToken=tokens[++index]
|
||||
return curToken
|
||||
|
||||
/*
|
||||
Class: nS_Parser
|
||||
An implmentation of a parser for n_Script.
|
||||
*/
|
||||
/n_Parser/nS_Parser
|
||||
var/n_scriptOptions/nS_Options/options
|
||||
/*
|
||||
Constructor: New
|
||||
|
||||
Parameters:
|
||||
tokens - A list of tokens to parse.
|
||||
options - An object used for configuration.
|
||||
*/
|
||||
/n_Parser/nS_Parser/New(tokens[], n_scriptOptions/options)
|
||||
src.tokens=tokens
|
||||
src.options=options
|
||||
curBlock=global_block
|
||||
return ..()
|
||||
|
||||
/n_Parser/nS_Parser/Parse()
|
||||
ASSERT(tokens)
|
||||
for(,src.index<=src.tokens.len, src.index++)
|
||||
curToken=tokens[index]
|
||||
switch(curToken.type)
|
||||
if(/token/keyword)
|
||||
var/n_Keyword/kw=options.keywords[curToken.value]
|
||||
kw=new kw()
|
||||
if(kw)
|
||||
if(!kw.Parse(src))
|
||||
return
|
||||
if(/token/word)
|
||||
var/token/ntok
|
||||
if(index+1>tokens.len)
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
continue
|
||||
ntok=tokens[index+1]
|
||||
if(!istype(ntok, /token/symbol))
|
||||
errors+=new/scriptError/BadToken(ntok)
|
||||
continue
|
||||
if(ntok.value=="(")
|
||||
ParseFunctionStatement()
|
||||
else if(options.assign_operators.Find(ntok.value))
|
||||
ParseAssignment()
|
||||
else
|
||||
errors+=new/scriptError/BadToken(ntok)
|
||||
continue
|
||||
if(!istype(curToken, /token/end))
|
||||
errors+=new/scriptError/ExpectedToken(";", curToken)
|
||||
continue
|
||||
if(/token/symbol)
|
||||
if(curToken.value=="}")
|
||||
if(!EndBlock())
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
continue
|
||||
else
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
continue
|
||||
if(/token/end)
|
||||
warnings+=new/scriptError/BadToken(curToken)
|
||||
continue
|
||||
else
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
return
|
||||
return global_block
|
||||
|
||||
/n_Parser/nS_Parser/proc/CheckToken(val, type, err=1, skip=1)
|
||||
if(curToken.value!=val || !istype(curToken,type))
|
||||
if(err)
|
||||
errors+=new/scriptError/ExpectedToken(val, curToken)
|
||||
return 0
|
||||
if(skip)NextToken()
|
||||
return 1
|
||||
|
||||
/n_Parser/nS_Parser/proc/AddBlock(node/BlockDefinition/B)
|
||||
blocks.Push(curBlock)
|
||||
curBlock=B
|
||||
|
||||
/n_Parser/nS_Parser/proc/EndBlock()
|
||||
if(curBlock==global_block) return 0
|
||||
curBlock=blocks.Pop()
|
||||
return 1
|
||||
|
||||
/n_Parser/nS_Parser/proc/ParseAssignment()
|
||||
var/name=curToken.value
|
||||
if(!options.IsValidID(name))
|
||||
errors+=new/scriptError/InvalidID(curToken)
|
||||
return
|
||||
NextToken()
|
||||
var/t=options.binary_operators[options.assign_operators[curToken.value]]
|
||||
var/node/statement/VariableAssignment/stmt=new()
|
||||
stmt.var_name=new(name)
|
||||
NextToken()
|
||||
if(t)
|
||||
stmt.value=new t()
|
||||
stmt.value:exp=new/node/expression/value/variable(stmt.var_name)
|
||||
stmt.value:exp2=ParseExpression()
|
||||
else
|
||||
stmt.value=ParseExpression()
|
||||
curBlock.statements+=stmt
|
||||
|
||||
/n_Parser/nS_Parser/proc/ParseFunctionStatement()
|
||||
if(!istype(curToken, /token/word))
|
||||
errors+=new/scriptError("Bad identifier in function call.")
|
||||
return
|
||||
var/node/statement/FunctionCall/stmt=new
|
||||
stmt.func_name=curToken.value
|
||||
NextToken() //skip function name
|
||||
if(!CheckToken("(", /token/symbol)) //Check for and skip open parenthesis
|
||||
return
|
||||
var/loops = 0
|
||||
while(TRUE)
|
||||
loops++
|
||||
if(loops>=6000)
|
||||
CRASH("Something TERRIBLE has gone wrong in ParseFunctionStatement ;__;")
|
||||
|
||||
if(!curToken)
|
||||
errors+=new/scriptError/EndOfFile()
|
||||
return
|
||||
if(istype(curToken, /token/symbol) && curToken.value==")")
|
||||
curBlock.statements+=stmt
|
||||
NextToken() //Skip close parenthesis
|
||||
return
|
||||
var/node/expression/P=ParseParamExpression()
|
||||
stmt.parameters+=P
|
||||
/*
|
||||
File: Parser
|
||||
*/
|
||||
/*
|
||||
Class: n_Parser
|
||||
An object that reads tokens and produces an AST (abstract syntax tree).
|
||||
*/
|
||||
/n_Parser
|
||||
var/index = 1
|
||||
/*
|
||||
Var: index
|
||||
The parser's current position in the token's list.
|
||||
*/
|
||||
/*
|
||||
Var: tokens
|
||||
A list of tokens in the source code generated by a scanner.
|
||||
*/
|
||||
var/list/tokens = new
|
||||
/*
|
||||
Var: errors
|
||||
A list of fatal errors found by the parser. If there are any items in this list, then it is not safe to run the returned AST.
|
||||
|
||||
See Also:
|
||||
- <scriptError>
|
||||
*/
|
||||
var/list/errors = new
|
||||
/*
|
||||
Var: warnings
|
||||
A list of non-fatal problems in the script.
|
||||
*/
|
||||
var/list/warnings = new
|
||||
/*
|
||||
Var: curToken
|
||||
The token at <index> in <tokens>.
|
||||
*/
|
||||
var/token/curToken
|
||||
var/stack/blocks=new
|
||||
var/node/BlockDefinition/GlobalBlock/global_block=new
|
||||
var/node/BlockDefinition/curBlock
|
||||
|
||||
/*
|
||||
Proc: Parse
|
||||
Reads the tokens and returns the AST's <GlobalBlock> node. Be sure to populate the tokens list before calling this procedure.
|
||||
*/
|
||||
/n_Parser/proc/Parse()
|
||||
|
||||
/*
|
||||
Proc: NextToken
|
||||
Sets <curToken> to the next token in the <tokens> list, or null if there are no more tokens.
|
||||
*/
|
||||
/n_Parser/proc/NextToken()
|
||||
if(index>=tokens.len)
|
||||
curToken=null
|
||||
else
|
||||
curToken=tokens[++index]
|
||||
return curToken
|
||||
|
||||
/*
|
||||
Class: nS_Parser
|
||||
An implmentation of a parser for n_Script.
|
||||
*/
|
||||
/n_Parser/nS_Parser
|
||||
var/n_scriptOptions/nS_Options/options
|
||||
/*
|
||||
Constructor: New
|
||||
|
||||
Parameters:
|
||||
tokens - A list of tokens to parse.
|
||||
options - An object used for configuration.
|
||||
*/
|
||||
/n_Parser/nS_Parser/New(tokens[], n_scriptOptions/options)
|
||||
src.tokens=tokens
|
||||
src.options=options
|
||||
curBlock=global_block
|
||||
return ..()
|
||||
|
||||
/n_Parser/nS_Parser/Parse()
|
||||
ASSERT(tokens)
|
||||
for(,src.index<=src.tokens.len, src.index++)
|
||||
curToken=tokens[index]
|
||||
switch(curToken.type)
|
||||
if(/token/keyword)
|
||||
var/n_Keyword/kw=options.keywords[curToken.value]
|
||||
kw=new kw()
|
||||
if(kw)
|
||||
if(!kw.Parse(src))
|
||||
return
|
||||
if(/token/word)
|
||||
var/token/ntok
|
||||
if(index+1>tokens.len)
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
continue
|
||||
ntok=tokens[index+1]
|
||||
if(!istype(ntok, /token/symbol))
|
||||
errors+=new/scriptError/BadToken(ntok)
|
||||
continue
|
||||
if(ntok.value=="(")
|
||||
ParseFunctionStatement()
|
||||
else if(options.assign_operators.Find(ntok.value))
|
||||
ParseAssignment()
|
||||
else
|
||||
errors+=new/scriptError/BadToken(ntok)
|
||||
continue
|
||||
if(!istype(curToken, /token/end))
|
||||
errors+=new/scriptError/ExpectedToken(";", curToken)
|
||||
continue
|
||||
if(/token/symbol)
|
||||
if(curToken.value=="}")
|
||||
if(!EndBlock())
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
continue
|
||||
else
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
continue
|
||||
if(/token/end)
|
||||
warnings+=new/scriptError/BadToken(curToken)
|
||||
continue
|
||||
else
|
||||
errors+=new/scriptError/BadToken(curToken)
|
||||
return
|
||||
return global_block
|
||||
|
||||
/n_Parser/nS_Parser/proc/CheckToken(val, type, err=1, skip=1)
|
||||
if(curToken.value!=val || !istype(curToken,type))
|
||||
if(err)
|
||||
errors+=new/scriptError/ExpectedToken(val, curToken)
|
||||
return 0
|
||||
if(skip)NextToken()
|
||||
return 1
|
||||
|
||||
/n_Parser/nS_Parser/proc/AddBlock(node/BlockDefinition/B)
|
||||
blocks.Push(curBlock)
|
||||
curBlock=B
|
||||
|
||||
/n_Parser/nS_Parser/proc/EndBlock()
|
||||
if(curBlock==global_block) return 0
|
||||
curBlock=blocks.Pop()
|
||||
return 1
|
||||
|
||||
/n_Parser/nS_Parser/proc/ParseAssignment()
|
||||
var/name=curToken.value
|
||||
if(!options.IsValidID(name))
|
||||
errors+=new/scriptError/InvalidID(curToken)
|
||||
return
|
||||
NextToken()
|
||||
var/t=options.binary_operators[options.assign_operators[curToken.value]]
|
||||
var/node/statement/VariableAssignment/stmt=new()
|
||||
stmt.var_name=new(name)
|
||||
NextToken()
|
||||
if(t)
|
||||
stmt.value=new t()
|
||||
stmt.value:exp=new/node/expression/value/variable(stmt.var_name)
|
||||
stmt.value:exp2=ParseExpression()
|
||||
else
|
||||
stmt.value=ParseExpression()
|
||||
curBlock.statements+=stmt
|
||||
|
||||
/n_Parser/nS_Parser/proc/ParseFunctionStatement()
|
||||
if(!istype(curToken, /token/word))
|
||||
errors+=new/scriptError("Bad identifier in function call.")
|
||||
return
|
||||
var/node/statement/FunctionCall/stmt=new
|
||||
stmt.func_name=curToken.value
|
||||
NextToken() //skip function name
|
||||
if(!CheckToken("(", /token/symbol)) //Check for and skip open parenthesis
|
||||
return
|
||||
var/loops = 0
|
||||
while(TRUE)
|
||||
loops++
|
||||
if(loops>=6000)
|
||||
CRASH("Something TERRIBLE has gone wrong in ParseFunctionStatement ;__;")
|
||||
|
||||
if(!curToken)
|
||||
errors+=new/scriptError/EndOfFile()
|
||||
return
|
||||
if(istype(curToken, /token/symbol) && curToken.value==")")
|
||||
curBlock.statements+=stmt
|
||||
NextToken() //Skip close parenthesis
|
||||
return
|
||||
var/node/expression/P=ParseParamExpression()
|
||||
stmt.parameters+=P
|
||||
if(istype(curToken, /token/symbol) && curToken.value==",") NextToken()
|
||||
Reference in New Issue
Block a user