astTestastTest - Test if an Object attribute value is set

Description:
This function returns a boolean result (0 or 1) to indicate whether a value has been explicitly set for one of an ObjectObject's attributes.
Synopsis:
int astTest( AstObject $*$this, const char $*$attrib )
Parameters:
this
Pointer to the Object.
attrib
Pointer to a null-terminated character string containing the name of the attribute to be tested.
Class Applicability:
Object
This function applies to all Objects.
Returned Value:
astTest()
One if a value has previously been explicitly set for the attribute (and hasn't been cleared), otherwise zero.
Notes:
  • Attribute names are not case sensitive and may be surrounded by white space.

  • A value of zero will be returned if this function is invoked with the AST error status set, or if it should fail for any reason.

  • A value of zero will also be returned if this function is used to test a read-only attribute, although no error will result.