query descendants
The reverse of query ancestors: lists every class that descends from a given ancestor, across all scanned databases.
Read this to answer what derives from this class. It lists every class that descends from a given ancestor across all scanned indexes; derived interfaces are left out on purpose.
How to run it
Full flag list: query in the CLI reference.
Flags
| Flag | Argument | Meaning | Default |
|---|---|---|---|
--of | <ancestor> | ||
--db | |||
--json |
Where to click
- RAD Studio main menu: drag-lint > Inspect Symbol > Descendants of Class...
Details
The reverse of query ancestors: lists every class
that descends from a given ancestor, across all scanned databases. Reach for it
to answer "what derives from this?" -- it is what fills the conversion editor's
control-class pickers.
Running it from the CLI
drag-lint query descendants --of <ancestor> [--db ...] [--json]--of <ancestor> is required; there is no --name form.
Classes only -- and that is deliberate
Derived interfaces are excluded. This verb backs class pickers, which must
never be offered an interface, so --of <an interface> lists the classes that
implement it and never the sub-interfaces that extend it.
That has a consequence worth knowing: an ancestor whose only descendants are
interfaces answers nothing. On the platform library,
query descendants --of IFIBObject prints no rows even though the index holds
IFIBConnect, IFIBSQLObject and IFIBTransaction.
If you want the interface side, hover the interface instead.
drag-lint hover --qname <Unit.IFoo> reports both, labelled separately:
- Implemented by: TFIBCustomDataSet, TFIBDatabase, ... (+14 more)
- Extended by: IFIBConnect, IFIBDataSet, IFIBQuery, IFIBSQLObject, IFIBTransactionExit codes
0 found at least one descendant ; 1 no such ancestor (not an error --
it is the answer) ; 2 usage error, or a stale/unusable --db.
The exit-1 case is load-bearing: an unconditional 0 would destroy the only
signal a caller has for "no such ancestor".
Reaching it in the IDE
No IDE surface -- CLI only. The conversion rules editor consumes it through the engine adapter.
What it needs
--db is optional; drag-lint auto-resolves the index when it is omitted. An
index must exist.
Example
Illustrative:
drag-lint query descendants --of TControl --db C:\Projects\.drag-lint\library-Win64.sqliteThis would list every TControl descendant in the Win64 platform library --
the set the conversion editor offers as conversion targets.