Syntax Typo?

[chrispminis]

Yeah, this isn't a big problem. I've just been staring at my code for about 40 minutes, and I still haven't found the problem. There are 2 errors. One is for a string literal that should end the line, the other is a syntax error expecting then.

code:

%Text Calculator %by : Chris Pan %Evaluates expressions by reading and interpreting strings %Don't Steal %Variables var stringy : string var number : real := 0 var mark, negmark : int var string1, string2 : string var dec, neg : boolean := false var maxsymbol : int := 10 type prioritize :     record         svalue : string         smark : int         spriority : int         sused : boolean     end record var symbol : array 1 .. maxsymbol of prioritize for i : 1 .. maxsymbol     symbol (i).svalue := " "     symbol (i).smark := 0     symbol (i).spriority := 0     symbol (i).sused := false end for %Functions function stringreal (str : string) : real     mark := index (str, ".")     negmark := index (str, "-")     if mark > 0 then         dec := true     end if     if negmark > 0 then         neg := true     end if     for i : 1 .. length (str)         if str (i) >= "1" and str (i) <= "9" then             number *= 10             number += (ord (str (i)) - 48)         end if     end for     if dec = true then         number := number / (10 ** (length (str) - mark))     end if     if neg = true then         number := -number     end if     result number end stringreal function add (num1, num2 : real) : real     result num1 + num2 end add function subtract (num1, num2 : real) : real     result num1 - num2 end subtract function multiply (num1, num2 : real) : real     result num1 * num2 end multiply function divide (num1, num2 : real) : real     result num1 / num2 end divide function power (num1, num2 : real) : real     result num1 ** num2 end power function squareroot (num1 : real) : real     result sqrt (num1) end squareroot function estimate (num1 : real) : int     result round (num1) end estimate function up (num1 : real) : int     result ceil (num1) end up function down (num1 : real) : int     result floor (num1) end down %Main %Input get stringy : * %Identify and Prioritize for i : 1 .. length (stringy)     if stringy (i) not= " " and stringy (i) < "0" or stringy (i) > "9" then         symbol (i).sused := true         symbol (i).svalue := stringy (i)         symbol (i).smark := i     end if end for for i : 1 .. length (stringy)     if symbol (i).sused = true then         if symbol (i).svalue = "q" or symbol (i).svalue = "h" then             symbol (i).spriority := 7         elsif symbol (i).svalue = "=" then             symbol (i).spriority := 6         elsif symbol (i).svalue = "~" or symbol (i).svalue = "<" or symbol (i).svalue = ">" then             symbol (i).spriority := 5         elsif symbol (i).svalue = "+" or symbol (i).svalue = "-" then             symbol (i).spriority := 4         elsif symbol (i).svalue = "x" or symbol (i).svalue = "X" or symbol (i).svalue = "*" or symbol (i).svalue = "/" then             symbol (i).spriority := 3         elsif symbol (i).svalue = "^" or symbol (i).svalue = "&" then             symbol (i).spriority := 2         elsif symbol (i).svalue = "(" then             symbol (i).spriority := 1         end if     end if end for %Test Output for i : 1 .. length (stringy)     if symbol (i).sused then         put symbol (i).svalue         put symbol (i).smark         put symbol (i).spriority     end if end for

Here's my code, I was just testing my prioritizing, for BEDMAS. I am sure the error is linked to an extra " somewhere but I can't find it! Please help.

[Delos]

code:

elsif symbol (i).svalue = "\^" or symbol (i).svalue = "&" then

Not sure if it achieves what you want it to though...

[chrispminis]

I'm not sure what you are trying to point me towards. But where did the "\^" come from?

Im trying to prioritize them, "&" is my chosen square root sign. So exponents and square root go to the same priority level.

[pavol]

im not sure, you have more knowledge in this matter than i do, but if you take ^ out of:

code:

elsif symbol (i).svalue = "^" or symbol (i).svalue = "&" then     symbol (i).spriority := 2

to make it:

code:

elsif symbol (i).svalue = "" or symbol (i).svalue = "&" then     symbol (i).spriority := 2

i know it probably doesn't make your program do what you want, but what i'm trying to point out is that maybe "^" is the problem and maybe it is some kind of thing held special by Turing and you're not really allowed using it.
hope it gives some insight into your problem

[Delos]

pavol is on the right track. '^' is a 'special thing' in Turing, but you are allowed to use it, provided you know how. In this case, if you wish to use it in a string, you need to provide the escape character '\' first. This is similar to using things like '\n' or '\"'.
I'm guessing the '^' would be for an exponent...

[MysticVegeta]

no ** is for exponent. ^ is reserved for other string purpose, and yes you would need to put "\" before the ^ so it would be "\^", its the same as saying "^", its for the same reason as for in java when you have to put "\\+" due to regex issues.

[Delos]

MysticVegeta wrote:

no ** is for exponent. ^ is reserved for other string purpose, and yes you would need to put "\" before the ^ so it would be "\^", its the same as saying "^", its for the same reason as for in java when you have to put "\\+" due to regex issues.

I meant in his proggie. You know, typing in "4^3" meaning four raised to the third power...

[chrispminis]

well, Ill try that, that makes sense. And Delos it is ** for exponent. Turing doesn't evaluate 2^3 = 8. Just another thing. If you wanted the backslash character (\) in a string would it be "\\"?

[[Gandalf]]

^ is the more 'universal' exponent representation, while ** is what Turing uses since ^ is reserved for other things.

Yes, to output a backslash you would use escape + \, or else "\\".

[Clayton]

i have to ask what do you mean by using backslash as an escape character? what is an escape character and what are they used for? i know this is off topic but i didnt want to start another thread just for this

[Delos]

Well, the most practical interpretation would be that you 'escape' from the literal string that you're using, and can implement a secondary command instead. So, for instance, you have "Hello /n World", which prints Hello and World on seperate lines. Since it's all in one string, the '/' allows you to drop out from the usual translation and actually do some manipulations.
This is rather limited though, since any more graphically-oriented procedures (Font. etc) don't support this (seeing as they create pictures). And of course, everyone loves pictures.