Code: Select all
'Print ABC
declare function BC (rv as string) as string
dim s as string
s="A"
s=BC(s)
?s
sleep
end
function BC (rv as string) as string
declare function c (rv as string) as string 'Apparently not legit
rv=rv+"B"
rv=c(rv)
BC=rv
end function
function C (rv as string) as string
rv=rv+"C"
C=rv
end function
Declarations must be done for each and every procedure (Sub/Function) before it can be called.Flyzone wrote:... I can't do it since the required DECLARE that is needed before using a function is prohibited within it.
Flyzone wrote:Got that?
Code: Select all
function BC (rv as string) as string
BC = rv
end functionCode: Select all
'Print ABC
declare function BC (rv as string) as String
Declare Function C (rv as string) as String
dim s as string
s="A"
s=BC(s)
?s
sleep : end
function BC (rv as string) as string
rv=rv+"B"
rv=c(rv)
BC=rv
end function
function C (rv as string) as string
rv=rv+"C"
C=rv
end functionHow do you think, the compiler knows what you "declare" first, second or other code-level ???Flyzone wrote:... but seems I shouldn't have to do that for lower level calls.
Well, at the risk of getting in trouble here, it should accept the DECLARE in the first lower level function (as I originally wrote in my first post) which would satisfy that requirement -- but it doesn't (It should) -- so I'll just have to live with that.MrSwiss wrote:How do you think, the compiler knows what you "declare" first, second or other code-level ???Flyzone wrote:... but seems I shouldn't have to do that for lower level calls.
Why? Declarations need to be put at the global scope; they're just that, declarations. FreeBasic, as many other BASIC dialects, does not support nested procedures. Also, you don't need to declare anything if you define before using. In your case:Flyzone wrote:Well, at the risk of getting in trouble here, it should accept the DECLARE in the first lower level function (as I originally wrote in my first post) which would satisfy that requirement -- but it doesn't (It should) -- so I'll just have to live with that.
Code: Select all
function C (rv as string) as string
rv=rv+"C"
return( rv )
end function
function BC (rv as string) as string
rv=rv+"B"
rv=c(rv)
return( rv )
end function
'Print ABC
dim s as string
s="A"
s=BC(s)
?s
sleep
end
Nope, won't work. The important part here is: compile.Flyzone wrote:Another thing I haven't tried is, and I am assuming that I could compile and store such functions in a linklib and reference procedures in similar fashion without declares and just an include filespec. Right?
I'm not sure what the source of your difficulties here is. Are you familiar with other languages? The way FB works is no different than C, for example. A bi file contains prototypes and structures that the user of a library needs to know in order to call the library functions. This includes the "declare function" and "declare sub" statements. The dll contains the actual implementation of the library functions and could be compiled from a completely different language like C. In short, how FB behaves is nearly identical to C where .bi files are called "header" .h files. Some C compilers may allow you to forward reference a function in the same source code unit (file) without an advance declaration. Others do not. I'm not able to determine what the C standard has to say on the matter, but all code I've ever looked at defines the function prototype before any forward references are made. Certainly to use any kind of library you need a header file or a .bi file to tell the compiler how to build the structures you'll need and tell the compiler what the function names are and how they are called.Flyzone wrote:Yes, I assumed compiled tho I guess I used the wrong terminology. So, a .bi file can be created and the function(s) then stored in a lib.bi somehow then referenced without fanfare in another source. Perhaps I need some sort of EXTERN statement (or not would be better) though there is still the matter of whether the DECLAREs would still be required or not.
I am used to using "old school" 2 pass compilers which were much more convenient and did all this stuff for you. With processors so fast and cheap today is seems to me we got it backwards with one-pass. Yes, they're faster but whose work are we trying to speed up? But that's just ole' me I guess...
You can't? You just mentioned two of them. There are others ...apparently Quick Basic had no issue with forward referencing a function without any sort of advanced declaration. FB does not allow that, nor can I think of a good reason to allow that.
QB and QBASIC automatically add the procedure declarations when the IDE saves the file. If you were to use an editor on the file directly or remove the declarations automatically saved, QB's command line compiler 'BC' would throw an error if the procedure was used without a declaration or or before definition.apparently Quick Basic had no issue with forward referencing a function without any sort of advanced declaration.