delphi-patterns

name	delphi-patterns
description	Coding conventions and patterns for the SimpleORM Delphi project. Automatically loaded when writing or modifying Delphi code.
user-invocable	false

SimpleORM Delphi Patterns

Rules are in .claude/rules/ — this skill provides patterns and templates, not rules.

Class Structure Template

TSimpleXxx = class(TInterfacedObject, iSimpleXxx)
private
  FField: Type;
public
  constructor Create(aParam: Type);
  destructor Destroy; override;
  class function New(aParam: Type): iSimpleXxx;
end;

Naming Reference

Element	Convention	Example
Unit	SimpleXxx.pas	SimpleDAO.pas
Class	TSimpleXxx	TSimpleDAO
Interface	iSimpleXxx (lowercase i)	iSimpleQuery
Exception	ESimpleXxx	ESimpleValidator
Field	F prefix	FQuery, FParams
Parameter	a prefix	aValue, aSQL
Local var	L prefix (new code)	LResult

Conditional Compilation Patterns

{$IFNDEF CONSOLE}    // UI code (forms, bindings)
{$IFDEF FMX}         // FireMonkey specific
{$IFDEF VCL}         // VCL specific
{$IF RTLVERSION > 31.0}  // Newer Delphi features

Uses Clause Organization

interface
uses
  // 1. SimpleORM units
  SimpleInterface, SimpleTypes,
  // 2. System units
  System.SysUtils, System.Classes, System.Generics.Collections,
  // 3. Data units
  Data.DB,
  // 4. Conditional UI units
  {$IFNDEF CONSOLE}
    {$IFDEF FMX} FMX.Forms, {$ELSE} Vcl.Forms, {$ENDIF}
  {$ENDIF}
  // 5. Driver-specific units last
  FireDAC.Comp.Client;

Error Handling Template

try
  FQuery.ExecSQL;
except
  on E: Exception do
  begin
    if FTransaction.Active then
      FTransaction.Rollback;
    raise;
  end;
end;

Destructor Template

destructor TSimpleXxx.Destroy;
begin
  FreeAndNil(FOwnedObject1);
  FreeAndNil(FOwnedObject2);
  // Interface fields: do NOT free (auto-managed)
  inherited;
end;

RTTI Helper Methods

Use helpers from SimpleRTTIHelper.pas:

• Portuguese (legacy): EhChavePrimaria, EhChaveEstrangeira, EhCampo, Tem<T>
• English (new): IsNotNull, IsIgnore, IsAutoInc, IsHasOne, HasFormat