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dev_error_vardev_error_varDevErrorVarDevErrorVar (Operator)


dev_error_vardev_error_varDevErrorVarDevErrorVar — Define or undefine an error variable.


dev_error_var( : : ErrorVar, Mode : )

Herror dev_error_var(const Hlong ErrorVar, const Hlong Mode)

Herror T_dev_error_var(const Htuple ErrorVar, const Htuple Mode)

void DevErrorVar(const HTuple& ErrorVar, const HTuple& Mode)

static void HOperatorSet.DevErrorVar(HTuple errorVar, HTuple mode)


dev_error_vardev_error_varDevErrorVarDevErrorVarDevErrorVar defines an error variable, i.e., a variable which contains the result state of the last operator call. ErrorVarErrorVarErrorVarErrorVarerrorVar will be 2 (H_MSG_TRUE) if no error had occurred. The parameter ModeModeModeModemode specifies whether the error variable should be used (1) or not (0). If an error variable is active it will be updated each time an operator execution is finished. Thus a value is only valid until the next call of an operator. The value can be saved by assigning it to another variable (see example) or by calling dev_error_var(ErrorVar,0)dev_error_var(ErrorVar,0)DevErrorVar(ErrorVar,0)DevErrorVar(ErrorVar,0)DevErrorVar(ErrorVar,0).


ErrorVarErrorVarErrorVarErrorVarerrorVar (input_control)  integer HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Name of the variable which shall contain the error status.

Default value: 'ErrorVar' "ErrorVar" "ErrorVar" "ErrorVar" "ErrorVar"

ModeModeModeModemode (input_control)  integer HTupleHTupleHtuple (integer) (int / long) (Hlong) (Hlong)

Switch the error variable on or off.

Default value: 1

List of values: 0, 1

Example (HDevelop)

dev_close_window ()
dev_open_window (0, 0, 512, 512, 'black', WindowHandle)
dev_error_var (Error, 1)
dev_set_check ('~give_error')
FileName := 'wrong_name'
read_image (Image, FileName)
ReadError := Error
if (ReadError != H_MSG_TRUE)
  write_string (WindowHandle, 'wrong file name: '+FileName)


If the values of the specified parameters are correct, dev_error_vardev_error_varDevErrorVarDevErrorVarDevErrorVar returns 2 (H_MSG_TRUE). Otherwise an exception is raised and an error code returned.

Possible Predecessors


Possible Successors

dev_set_checkdev_set_checkDevSetCheckDevSetCheckDevSetCheck, ififIfIfIf, elseifelseifElseifElseifElseif, elseelseElseElseElse, assignassignAssignAssignAssign

See also

dev_set_checkdev_set_checkDevSetCheckDevSetCheckDevSetCheck, set_checkset_checkSetCheckSetCheckSetCheck