Why doesnt this work?
BlitzMax Forums/BlitzMax Beginners Area/Why doesnt this work?
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Local T:String T = "h" While Not T=Chr(34) Print "Made it" T=Chr(34) Wend It should print out "Made it" but it doesnt. Any ideas? It only seems to do it with the quote character (tried using "~q" and such, and it does the same) |
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| Hmm. I'm not sure why its not working as is but putting brackets around T=Chr(34) works. You should use "~q" now though. |
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Local T:String While Not (T=Chr(34)) Print "Made it" T=Chr(34) Wend It's the Not |
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| Hmm. I'm not sure why its not working as is but putting brackets around T=Chr(34) works. You should use "~q" now though. "~q" doesnt work either |
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| The problem is that Not has higher precedence than = so it is done first. There is a table of operator precedence in the Expressions section of the Language Reference. |
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| But then it isn't basic compadible.... It is a 'not' comparisson, standard basic true/false evaulation. How can one 'expect' a program to operate a certain way if it doesn't follow a standard set of rules. |
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| I posted a solution higher up. You need to put brackets around the operations you want to perform before Not is applied. as it was originally, you were effectively doing: While (Not T) = Chr(34) and since (Not T) will never = chr(34) it is never run. |
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| How can one 'expect' a program to operate a certain way if it doesn't follow a standard set of rules. I don't think there is any standard set of rules. For example, C and Pascal both give their 'not' operators higher precedence than comparisons. Actually, I have complained about And/Or having the same precedence. But nothing changed then so I wouldn't expect any changes now. |
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| thanks for the 'workaround' there Perturbatio. I do appreciate it, however it still dissapoints me a bit. The more I think the basic code of Blitz can port (for the most part) to blitzmax, the more I find I am mistaken and must re-write/re-learn how to program. I agree there Floyd, however in C you can say if(d!=1) and it works.the () are requirements of the C language. Where with blitz I now have to encapsulate everything in () and hope I am correct as to the way it 'should' evaluate in refference to the way it 'actually' evaluates. I have always encapsulated and/or clauses with () since in most basic languages they have the same precedence, however one would hope that in an evaluation the compiler would check for a preceeding expression before assuming it has completed the evaluation. One would hate it if you said a=5+5 and have the compiler merely return 5 to 'a' and syntax error the '+5'. Perhaps we should be using the '==' instead :-( |
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| Uh, what? I posted the answer first but oh well. Maybe you didnt undersand "brackets". Not having higher precendence than a comparison makes no sense at all. This is what i thought at first was going on, but I disregarded it because I thought that blitz would say you cant compare an integer (result of a boolean) to an object. <edit>Although, on second thought you should never have to use not like this. Just replace the = with <> and take out the not. |
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| Uh, what? I posted the answer first but oh well. Maybe you didnt undersand "brackets". I understood brackets perfectly well, I must have over looked your post because of how small it was in comparrison to the two around it (my bad). Although, on second thought you should never have to use not like this. Just replace the = with <> and take out the not. Yeah, I started using the <> just after making this thread. But what do you mean on never having to use not like this? I thought the evaluation was pretty straight forward. |
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| Well, you never have to use not on a comparison because all the comparisons have inverses. (like > and <=, < and >=, = and <>) |
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