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X Macro

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photon3108:
Does the autocomplete of CodeBlocks support X Macro?

ollydbg:
What does "X Macro" means?

photon3108:
http://en.wikipedia.org/wiki/X_Macro

It's a C marco skill. Some people use it to generate the code of enum and array in compile-time.
Because they generate enumerator in compile-time, I can't use autocomplete to select it.

ollydbg:
OK, I see.
The reason is that our parser(preprocessor) don't do a semantic check on every identifier, CB has macro expansion method, but it does not expand macro usage always.
For example, when the parser see a identifier like token:

--- Code: ---LIST_OF_VARIABLES

--- End code ---
It just see it as a simple type name or a variable name.

But what a compiler(gcc) do is to check every identifier to see whether it is a macro usage, and if it is true, then expand the macro.

I think we can enable it, but it will let the parser a bit slower, as you can think, checking of every identifier token takes much time, right?
Here is a test (cctest) file that we can test your request:

--- Code: ---/* x macro
 * https://en.wikipedia.org/wiki/X_Macro
 */


#define LIST_OF_VARIABLES \
    X(value1) \
    X(value2) \
    X(value3)

#define X(name) int name;
LIST_OF_VARIABLES
#undef X

// val  //value1,value2,value3

--- End code ---

Currently, it get failed, but if we try to expand the LIST_OF_VARIABLES, I think it should be OK.

Also, for some enum definition:


--- Code: ---// test parsing of enumerator assignments


#define SHIFT(_x) (1 << (_x))
enum PowerEnum
{
    powFirst    = SHIFT(1),
    powSecond   = SHIFT(2),
    powThird    = SHIFT(3),
    powFourth   = SHIFT(4),
    powFifth    = SHIFT(5)
};

--- End code ---
the value is calculated, because we enable the macro expansion on enumerator definition. So you will see such tip: (image shot below)



You see, the tip show a value 32, which is calculated "1<<5".

Maybe, we can trigger macro expansion on a token which is totally capital characters?

Huki:

--- Quote from: ollydbg on March 05, 2014, 04:11:13 am ---I think we can enable it, but it will let the parser a bit slower, as you can think, checking of every identifier token takes much time, right?
Here is a test (cctest) file that we can test your request:

--- Code: ---/* x macro
 * https://en.wikipedia.org/wiki/X_Macro
 */


#define LIST_OF_VARIABLES \
    X(value1) \
    X(value2) \
    X(value3)

#define X(name) int name;
LIST_OF_VARIABLES
#undef X

// val  //value1,value2,value3

--- End code ---

Currently, it get failed, but if we try to expand the LIST_OF_VARIABLES, I think it should be OK.

--- End quote ---
This feature is present in my cc_parser_general.patch (checks each identifier for preprocessor token if the m_Options.parseComplexMacros is on). It's a rather long patch with several other features, I'm trying to get the small ones (and bug fixes) in first. :)

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