This topic describes methods of calling items declared in another unit with DelphiScript code.
Adding Script References
To reference another unit from the current unit using DelphiScript, add the following line at the beginning of the current script (before any functions and variable declarations):
// To reference one unit
// To reference multiple units
uses UnitName1, UnitName2;
Calling Items From Another Unit
Once an external unit is linked to the current one, all the routines, as well as global variables and constants of the external unit, can be called in the current unit. It is recommended, though not obligatory, to prefix the names of external routines, variables and constants with the unit's name. That is, in general, calling items from another unit with any of the following code instructions is correct:
You must specify the name of the referenced unit in the following cases:
When the current unit already contains a routine, global variable or global constant with the same name. Without prefixing, the routine, variable or constant of the current unit will be called.
When the name of an external routine is the same as the name of an external unit. Calling such a routine without a prefix will cause an exception.
When calling routines, variables or constants declared in a third unit.
To call a routine defined in an external unit that is linked to your current unit, you can also pass a string that specifies the target routine’s full name (that is, "unit_name.routine_name") to the
Evaluate function. If the external routine you want to call takes parameters, include them into the string parameter you pass to the eval functions.
Evaluate('UnitB.TestProcedure(1, ''string'', true)');
res := Evaluate('UnitB.TestFunction');
To make a variable or constant visible to other units, declare it as global, that is, outside any routines.
If the current unit is linked to a unit that is linked to another unit, the script declared in the third unit can be called from the current unit. For instance, if you need to call a function declared in UnitA from UnitC, which is linked to UnitB, you must add references to UnitA in UnitB. They will interact in the following way:
UnitA (contains no references)→
UnitB (contains a reference to unitA)→
UnitC (contains a reference to unitB)
If the references are correct, the items from UnitA will be available in UnitC, like in the following example:
Log.Message('The procedure is run.');
Scripts declared in a fourth unit and greater cannot be called in the current unit using DelphiScript.
DelphiScript allows script units to refer to each other using circular references. For instance, if you need to call scripts declared in UnitA from UnitB, and to call scripts declared in UnitB from UnitA, you must add references to both units.
USEUNITstatement does not import, share or merge project items. So, these elements remain available only for the project the unit is imported from. To be able to work with elements that reside within external projects, you may need to import them to or share them with the current project that uses the unit. For more information about this, see Sharing Project Items and Their Child Elements Among Several Projects.
If you reference a script from another project, and that script uses object names from Name Mapping, you may need to merge the external Name Mapping file with your local Name Mapping file. For instructions, see Merge Name Mapping Files.