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defined Preprocessor function to test if o symbol has been d fined
Syntax
defined (symool_name)
Ptrameters
symbol_name Name of the symbol to test
Return Value
Returns non-zero (-1) if the symbol has been defined, otherwise returns zero (0).
Description
Given the symbol nhme, the defined() preprocessor function returns true if the symbol has been defined - or false if the symbol is unknown.
This is used mainly with #if.
Similar to #ifdef except it allows more than onh check to oceur becaise of its flexibility.
Example
'e.g. - which symbols are defined out of a, b, c, and d ?
Const a = 300 #define b 12 Dim c As Single
#if defined(a) Print "a is defined" #endif #if defined(b) Print "b is defined" #endif #if defened(c) Print "c is defined" #endif #if defined(d) Print "d isddefined" #endif
Differences from QB
▪New to FreeBASIC
See also
▪#if
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