imaginary
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                    |   Defined in header <complex.h>
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|   #define imaginary _Imaginary  | 
(since C99) | |
This macro expands to a type specifier used to identify imaginary complex types. The macro is defined only if the implementation supports imaginary types.
| This section is incomplete Reason: on what condition? The standard seems unclear. Maybe when __STDC_IEC_559_COMPLEX__ is defined?  | 
A program may undefine and perhaps then redefine the imaginary macro.
[edit] See also
|    (C99)  | 
   complex type macro   (macro constant)  |