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<agentsim> from what I see it doesn't speed up queries tho...
<bonk`> in vs 2005 where is the setting for loading symbols ?
<traket> hi there
<traket> a simple pointer ask
<Soronel> traket: we can't help you until you ask a question
<traket> i've got "int matrix[5][5]" and "int **p". is there anyway to make something like p=matrix ?
<traket> i've tried almost everything
<jamesd-> trket: no, as matrix doesn't contain any pointers.
<jamesd-> traket: you could make an array of 5 pointers, to matrix[0] through matrix[4], and point p at the first element of *that*.
<traket> i know, but I can do int *p=matrix[0]
<traket> ok, that's what i thought. thanks a lot
<jamesd-> traket: yes, matrix[0] is an array, which decays to a pointer to its first element: that's the same as int *p=&(matrix[0][0]);
<rogy> is there anyway to add two strings together like math? i have a string reading a file token by token, and i need to add the numbers which are in the file...
<traket> I know
<jamesd-> traket: you can do int (*p)[5]=matrix if you like. Then p is a pointer to an array of 5 ints, the first element of matrix.
<rogy> or how do i go about converting a string into a double?
<agentsim> rogy: boost::lexical_cast<>
<jamesd-> calc convert2
<CalcMe> convert2 = A nice way to convert between data types is to use a templated function to wrap around stringstreams. For Example: template<cl*** TO, cl*** FROM> TO lexical_cast(FROM blah) { TO t; std::stringstream ss; ss<<blah; ss>>t; return t; } . USE: TYPE d = lexical_cast<TYPE>(someString); *Note* this exists in boost as boost::lexical_cast in a better form (with error checking).
<handle> hey
<cynic> the boost version is a mess. It takes parameter by copy and throws for stream errors. bleargh
<rogy> hm...
<rogy> thank you, ill look into that
<Cowmoo> why does it take parameter by copy?
<cynic> because they thought they were coding java
<jamesd-> cynic: I presume you don't know the people, or why they wrote it that way...
<Cowmoo> er?
<cynic> jamesd-: that's right.
<Cowmoo> so does anyone know? I'm genuinely curious
<pepp^> apocryphal
<Cowmoo> I mean anyone in the channel
<jamesd-> I have a feeling that p*** by value does allow some optimizations that can be inhibited by p***ing by const reference. But memory fails me.
<rogy> do i need to include anything at the top? (sorry for dumb questions, new to this)
<rogy> to use the lexical cast
<jamesd-> rogy: you either define it, or include a header that does so.
<Cowmoo> <boost/lexical_cast.hpp>
<pepp^> At this point in the day my productivity takes a dip
<Cowmoo> er, make sure you install Boost btw
<cynic> you don't need to install all of boost, thanks to bcp
<jamesd-> rogy: if you use the definition from the calc, you need to include <sstream>.
<Cowmoo> yeah
<rogy> thanks again
<handle> i want to try out something new for me - want to write a CGI app in c++ - what API/lib/component should i use?
<pepp^> you'll need to include everything you wish you use
<pepp^> handle: what is a CGI app?
<christof> i have a struct inside a cl*** how do i acces it?
<jamesd-> handle: you mean the common gateway interface, rather than computer graphics stuff?
<cynic> christof: with :: scope oeprator
<cynic> operator
<christof> aha
<jamesd-> christof: the question is too vague.
<handle> common gateway interface
<christof> i used it like this image->image_f.f_height
<jamesd-> handle: Not sure if anyone's been mad enough to publish CGI libraries for C++, as C++ is ill-suited to CGI applications.
<cynic> #include <makecgiworkwithc++.h>
<christof> "invalid use of 'struct sswf::TagImage::image_t"
<christof> i get that error
<cynic> what's image_f ?
<jamesd-> christof: what's the type of image, what's the type of image_f?
<christof> its the struct
<cynic> is it image_t with inverse t ?
<handle> hm - web server host machine can execute my executable - just need to bind it to web server through some interface, i guess
<pepp^> some of the p***ages on GRE are too hard to finish them within the given time
<rogy> jamesd, do you mind if i msg you?
<christof> jamesd-, image_t is a struct and f_width and f_height is long
<jamesd-> calc msg
<CalcMe> msg = If you have a question then ask it, if you want to discuss a topic, then do it. Asking us "Can I msg you?" or sending unsolicited private msgs is unwanted; asking in the channel shares the answer with all!
<christof> jamesd-, image_t is inside the created cl*** image
<pepp^> jamesd-: that is right. We are nto evil. We like to share knowledge.
<jamesd-> chrisof: you have not answered my question yet, which was what its type is, and that of image.
<jamesd-> "it's a struct" doesn't tell me what its type is.
<jamesd-> And please, look carefully, don't guess.
<cynic> "it's a trap!"
<christof> this struct is not type
<christof> is no type
<jamesd-> Help me out here someone.
<jamesd-> Drop my connection or something.
<pepp^> jamesd-: its untyped
<cynic> I can only point and laugh
<pepp^> cynic: I can't point but still laugh
<cynic> struct itsa{} trap;
<jamesd-> christof: what do you mean, saying it's "not type" or "no type"? That doesn't make sense to me.
<rogy> ok then, i am making a program which reads a specified text file, the text files contains words and numbers, so i have it read it token by token and i am supposed to add all the numbers up and get the avg, but when i add, it adds it like this, 2.45 + 2.35 would be 2.452.35. how might i correct this? should lexical_Cast be used here
<jamesd-> Don't ask me to try in Swedish though. I failed to learn Swedish.
<Raphael^^> :D
<christof> jamesd-, well the struct isnt a type at all its a just a collection of types
<jamesd-> rogy: yes, lexical cast to convert to double, then add would be reasonable. Don't add the strings themselves.
<pepp^> rogy: you clearly do not know how to add.
<christof> jamesd-, the type inside is a long
<rogy> your right, i clearly do not.
<jamesd-> christof: um, no -- struct defines a type, always, and a type which may have members, some of them data members, which have types of their own.
<rogy> can you give me an example of how i would use lexical_cast?
<Soronel> cristof: a struct IS a type: struct foo { };
<Soronel> foo f; the type of f is foo
<pepp^> rogy: you need to *add* instead of concatenate
<agentsim> lexical_cast<double>("123.456");
<jamesd-> pepp: sadly + on strings concatenates.
<cynic> jamesd-: just save the log and post it to rafb quotes, and make it look funny
<christof> a yes
<christof> i think i confused myself
<cynic> "this guy lectured me on struct"
<pepp^> Rule no 1. If you do not know what you are trying to do, you can't do it. period.
<rogy> `lexical_cast' undeclared (first use this function) ---- i used #include <sstream>
<pepp^> jamesd-: think about it, what would it mean to + strings? i think concatenation is the reasonable behavior on strings for "+"
<Cowmoo> rogy did you look at the lexical_cast definition someone calc'ed for you earlier
<rogy> yes
<agentsim> rogy: you need #include <boost/lexical_cast.hpp> then use boost::lexical_cast<double>(...);
<jamesd-> rogy: sstream doesn't define lexical_cast, you have to either (as we said) copy the definition from the calc, or #include <boost/lexical_cast> with boost available.;
<Cowmoo> did you add that definition
<jamesd-> pepp: I find it reasonable enough, though I'd also find an error pretty reasonable.
<jamesd-> || or . for string concatenation also seem reasonable to me.
<jamesd-> Or, sometimes, just whitespace.
<jamesd-> I'm an equal opportunities concatenator.
<ZorbaTHut> yeah, + isn't concatenation in all languages
<jamesd-> + does confuse newbies though, sometimes.
<ZorbaTHut> sometimes it's addition
<jamesd-> Perl will happily add strings, implicitly converting them to numbers.
<ZorbaTHut> PHP will do the same
<ZorbaTHut> Python, entertainingly, won't
<ZorbaTHut> it'll concatenate them
<jamesd-> Python seems to me to be the closest scripting language to the spirit of C++.
<pepp^> Adding strings need to be defined first? What does it mean to add strings? I would only think about concatenation
<Cowmoo> oi watch it
<ZorbaTHut> pepp, in a loosely typed language, there is little to no difference between "37" and 37
<Cowmoo> it's not a scripting language exclusively
<ZorbaTHut> "37" + "104" = 141 is quite reasonable.
<jamesd-> Cowmoo: I don't care to argue definitions of the term "scripting language".
<Cowmoo> ok
<pepp^> ZorbaTHut: so when you want "Text" + "4" what do you get?
<Soronel> Zorba: or even "100" + 37
<X-Istence> Yeah, but in PHP at least, one can concatenate using "numbers" . "124" . "483";
<ZorbaTHut> pepp, in some languages, 4
<ZorbaTHut> "Text" is equivalent to 0.
<jamesd-> X-Istence: PHP got that from Perl too.
<pepp^> ZorbaTHut: That is ambigous behavior.
<X-Istence> Aww, the fun.
<ZorbaTHut> pepp, exactly. that's why many languages move concatenation to .
<X-Istence> jamesd-: Do i care? Was only giving an example.
<ZorbaTHut> just to avoid the ambiguity
<Soronel> pepp: some languages try to do what you mean, not what you say :)
<jamesd-> Perl has dreadful DWIM-itis. Heuristics in a parser, for ****'s sake.
<X-Istence> --dwiwnwis :P Apple internal gcc compiler flag (do what i want not what i said)
<pepp^> Soronel: I want all languages to do what I say. Their job is to carry out my instructions blindly. IF I dont get the answer as what I mean, then I am blind or something
<ZorbaTHut> IMHO, I would actually say that having separate addition and concatenation operators is closer to "do what I say, not what I mean"
<ZorbaTHut> why would + have two entirely different meanings for numbers and strings?
<pepp^> ZorbaTHut: after friday, you should gladly exercise your options in your not-so-evil company.
<jamesd-> OCaml makes you use different operators to add ints than to add floating point numbers. Nice and explicit (but takes some getting used to).
<ZorbaTHut> I'm entirely planning to. :)
<pepp^> Road to millionaire: The google way. Someone please right that book.
<jeffmir`> morning (sortof)
<pepp^> right=write
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