[Overview][Constants][Types][Classes][Procedures and functions][Variables] Reference for unit 'System' (#rtl)

Assert

Check validity of a given condition.

Declaration

Source position: line 0

procedure Assert(

  Expr: Boolean

);

procedure Assert(

  Expr: Boolean;

  const Msg: String

);

Description

With assertions on, Asserttests if expris false, and if so, aborts the application with a Runtime error 227 and an optional error message in msg. If expris true, program execution continues normally. If assertions are not enabled at compile time, this routine does nothing, and no code is generated for the Assertcall. Enabling and disabling assertions at compile time is done via the \$Cor \$ASSERTIONScompiler switches. These are global switches. The default behavior of the assert call can be changed by setting a new handler in the AssertErrorProcvariable. Sysutils overrides the default handler to raise a EAssertionFailedexception.

Errors

None.

See also

Halt

  

Stop program execution.

Runerror

  

Generate a run-time error.