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Old 09-18-2004, 09:01 PM   #1
abs
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global const int X = DEFINED (shows value in debugger?)


hi
i read that if u #DEFINE a value u use, in a debugger, it'll show up with it's value and not it's name (so may be hard to identify from other values if they're the same)

but if u use const x = 10, u always see 10 as x (so u know what the reference is to.)

if i want to do the second thing and i've already got a #DEFINED var i want to use...
Code:
#define SOME_HASH_DEFINED_VAR 10
global const int X = SOME_HASH_DEFINED_VAR;
will i see X as 10, X as X or X as SOME_HASH_DEFINED_VAR (this last one won't occur, right?)

ty
abs
 
Old 09-18-2004, 09:24 PM   #2
itsme86
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#define'd constants are replaced by their value by the preprocessor, so the compiled binary never even knows the name. On the other hand, a global const value get its symbol (name) placed inside the compiled binary so the debugger can look it up.
 
Old 09-25-2004, 11:09 AM   #3
abs
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yeah i know, that's why i asked.

so X will get it's symbol looked up and reported back as 10, right? SOME_HASH_DEFINED_VAR gets replaced by 10 (doesn't exist) in the symbol list from that point on or after all the precompiler statements are executed?

i.e. i can change existing programs
#DEFINE VAR VAL
to
#DEFINE OLDVAR VAL (prepend with 'OLD')
global const VAR = OLDVAR;

or undef the defined VAR and then define VAR as a global const. don't wanna do that coz it means i need to go to the place it's re-defined and enter it's value, or swap or whatever. this one provides all i need in one line.

and i can continue to change the value at the same place.

Last edited by abs; 09-25-2004 at 11:14 AM.
 
  


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