IsConstant?

[dedndave]

it is an equate
when the assembler sees it, it simply replaces it with the constant numeric value (or string, in the case of text)
the linker (and, thus, the exe) know nothing of the equate, unless you somehow force it to

[qWord]

mhh..
you want to know this at runtime (? that is also what you ask in your first post). This can only be done, if you record the EQU's names (this is makeable with macros) and save them as strings.

PS: I'm also not an native English speaker  :8)

[Nordwind64]

Hey cool, that seems to work...

Code Select Expand

IFDEF WM_PAINT
 PrintDec 1
ELSE
 PrintDec 0
ENDIF


I will test this extensively!

[Nordwind64]

Wow, that works fine! It is possible.  :U

Code Select Expand

  IFDEF WM_PAINT
   PrintDec 1
  ELSE
   PrintDec 0
  ENDIF
 
  IFDEF TDX_JWCZIGRE
   PrintDec 1
  ELSE
   PrintDec 0
  ENDIF
 
  IFDEF LVM_APPROXIMATEVIEWRECT
   PrintDec 1
  ELSE
   PrintDec 0
  ENDIF


Gives me:

1
0
1

But I could not geht it working as macro. How must I change it to work as macro? Macros are not my strength.  :P

[qWord]

Code Select Expand


MacroName macro txt:=<>
IFDEF txt
PrintDec 1
ELSE
PrintDec 0
ENDIF
endm


[Nordwind64]

Thank you to everybody which have helped me. Particularly to qWord!  :U
I would not have thought that an easy solution is possible.  :thumbu

edit > But if you mean to detect if constant is defined in include files
& tell that at run time :} wow  .. there is no easy way | unless you wanna make a parser :}

I need this for writing a parser.  :lol

[Nordwind64]

Ok, the macro works perfekt with plaint texts like:

Code Select Expand


IsConst macro txt:=<>
  IFDEF txt
    mov eax,1
  ELSE
    xor eax,eax
  ENDIF
endm

...

IsConst WM_PAINT

Is it possible to get it working with an address of a string?

Code Select Expand

lea ecx,text
IsConst ecx

[dedndave]

i don't know about that one
in the old days, equates had to be resolved on the first pass of the assembler
the addresses are not resolved until the second pass
the newer assemblers may be different

[jj2007]

Is it possible to get it working with an address of a string?

Code Select Expand

lea ecx,text
IsConst ecx

No. You test for ecx, a register. Its content is known only at runtime, and may correspond to an immediate like offset MyString, but that immediate will always "exist", since it's part of your address space.

If, however, you want to check whether MyString has been defined, it can be done:

Code Select Expand

ChkIsValidAddress MACRO arg
ifndef <arg>
  EXITM <1>
else
  EXITM <0>
endif
ENDM

EDIT: However, this still does not allow you to use an undefined MyString in your code. To achieve that, some more effort is needed:

Code Select Expand

include \masm32\include\masm32rt.inc

ChkIsValidAddress MACRO arg
  xor ecx, ecx
  ifdef arg
dec ecx
  else
.data
tmp$ CATSTR <arg>, < db "Hello everybody!", 13, 10, 0>
% echo tmp$
tmp$
.code
  endif
  mov eax, offset &arg&
  EXITM <ecx>
ENDM

.data
MyString db "Good morning, I am a defined string", 0

.code
start:
.if ChkIsValidAddress(MyString)
print eax, 13, 10
.else
print "No MyString", 13, 10
.endif

.if ChkIsValidAddress(MyUndefinedString)
print eax, 13, 10
.else
push eax
print "There was no MyUndefinedString", 13, 10, "but now there is one: "
pop eax
print eax
.endif

getkey
exit

end start


[Nordwind64]

 :'(

Ok, seems that cannot work. So I will go parsing the include-files.  ::)
Thank you to everybody which wanted to help me!  :U