# Directive #error

Directive #error

  `#error`

Description

  Throw an error during preprocessing.

  This directive causes a cpp error. It can be used to notify the user that certain functions are missing and similar things.

Note

  Note that this directive will cause `cpp()` to throw an error at the end of preprocessing, which will cause any compilation to fail.

Example

      #if !constant(Yp)
        #error Support for NIS not available.
        #endif

See also

  #warning