Inside Macintosh: Interapplication Communication /

Chapter 10 - Scripting Components / Scripting Components Reference

Optional Scripting Component Routines / Coercing Script Values

OSACoerceToDesc

You can use the OSACoerceToDesc function to coerce a script value to a descriptor record of a desired descriptor type.

FUNCTION OSACoerceToDesc(scriptingComponent: ComponentInstance;
                         scriptValueID: OSAID; 
                         desiredType: DescType;
                         modeFlags: LongInt;
                         VAR result: AEDesc): OSAError;

scriptingComponent

A component instance created by a prior call to the Component Manager function OpenDefaultComponent or OpenComponent (see page 10-4).

scriptValueID

The script ID for the script value to coerce.

desiredType

The desired descriptor type of the resulting descriptor record.

modeFlags

Information used by individual scripting components. To avoid setting mode flag values, specify kOSAModeNull.

result

The resulting descriptor record.

DESCRIPTION

The OSACoerceToDesc function coerces the script value identified by scriptValueID to a descriptor record of the type specified by the desiredType parameter, if possible. Valid types include all the standard descriptor types defined in the Apple Event Registry: Standard Suites, plus any special types supported by the scripting component.

SPECIAL CONSIDERATIONS

If you want the descriptor type of the descriptor record returned in the result parameter to be the same as the descriptor type returned by a scripting component, use OSACoerceToDesc and specify typeWildCard as the desired type. If you want to get a script value in a form that you can display for humans to read, use OSADisplay.

RESULT CODES

noErr	0	No error
errOSASystemError	-1750	General scripting system error
errOSAInvalidID	-1751	Invalid script ID
badComponentInstance	$80008001	Invalid component instance

SEE ALSO

For a description of OSADisplay, see page 10-35.