*IF ELSE ELSEIF ENDIF/de
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= (**COPIED FROM ENGLISH PAGE**) === Action
Conditional compilation directives intended for conditional compilation.
Syntax
#IF condition
#ELSEIF condition
#ELSE
#ENDIF
Remarks
Conditional compilation is supported by the compiler.
What is conditional compilation?
Conditional compilation will only compile parts of your code that meet the criteria of the condition.
By default all your code is compiled.
Conditional compilation needs a constant to test.
So before a condition can be tested you need to define a constant.
CONST test = 1
#IF TEST
Print "This will be compiled"
#ELSE
Print "And this not"
#ENDIF
Note that there is no THEN and that #ENDIF is not #END IF (no space)
You can nest the conditions and the use of #ELSE and #ELSEIF is optional.
There are a few internal constants that you can use. These are generated by the compiler:
_CHIP = 0
_RAMSIZE = 128
_ERAMSIZE = 128
_SIM = 0
_XTAL = 4000000
_BUILD = 11162
_CHIP is an integer that specifies the chip, in this case the 2313
_RAMSIZE is the size of the SRAM
_ERAMSIZE is the size of the EEPROM
_SIM is set to 1 when the $SIM directive is used
_XTAL contains the value of the specified crystal
_BUILD is the build number of the compiler.
The build number can be used to write support for statements that are not available in a certain version :
#IF _BUILD >= 11162
s = Log(1.1)
#ELSE
Print "Sorry, implemented in 1.11.6.2"
#ENDIF
Conditional compilation allows you to create different versions of your program but that you keep one source file.
For example you could make a multi lingual program like this :
CONST LANGUAGE=1
'program goes here
#IF LANGUAGE=1
DATA "Hello"
#ENDIF
#IF LANGUAGE=2
DATA "Guten tag"
#ENDIF
By changing the just one constant you then have for example English or German data lines.
Conditional compilation does not work with the $REGFILE directive. If you put the $REGFILE inside a condition or not, the compiler will use the first $REGFILE it encounters. This will be changed in a future version.
A special check was added to 1.11.8.1 to test for existence of constants or variables.
#IF varexist("S")
'the variable S was dimensioned so we can use it here
#ELSE
'when it was not dimmed and we do need it, we can do it here
DIM S as BYTE
#ENDIF
See Also
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