fcl-passrc

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This package contains some useful units for dealing with Pascal source files: Parsing, creating structures in memory, and output to files.

Used by: fpdoc

Units

Unit Comment
pastree Pascal parse tree classes, for storing a complete Pascal module in memory.
paswrite A class and helper functions for creating Pascal source files from parse trees
pparser Parser for Pascal source files. Reads files via the pscanner unit and stores all parsed data in a parse tree, as implemented in the pastree unit.
pscanner Lexical scanner class for Pascal sources

An example

{$mode objfpc}{$H+}

uses SysUtils, Classes, PParser, PasTree;

type
  { We have to override abstract TPasTreeContainer methods.
    See utils/fpdoc/dglobals.pp for an implementation of TFPDocEngine,
    a "real" engine. }
  TSimpleEngine = class(TPasTreeContainer)
  public
    function CreateElement(AClass: TPTreeElement; const AName: String;
      AParent: TPasElement; AVisibility: TPasMemberVisibility;
      const ASourceFilename: String; ASourceLinenumber: Integer): TPasElement;
      override;
    function FindElement(const AName: String): TPasElement; override;
  end;

function TSimpleEngine.CreateElement(AClass: TPTreeElement; const AName: String;
  AParent: TPasElement; AVisibility: TPasMemberVisibility;
  const ASourceFilename: String; ASourceLinenumber: Integer): TPasElement;
begin
  Result := AClass.Create(AName, AParent);
  Result.Visibility := AVisibility;
  Result.SourceFilename := ASourceFilename;
  Result.SourceLinenumber := ASourceLinenumber;
end;

function TSimpleEngine.FindElement(const AName: String): TPasElement;
begin
  { dummy implementation, see TFPDocEngine.FindElement for a real example }
  Result := nil;
end;

var
  M: TPasModule;
  E: TPasTreeContainer;
  I: Integer;
  Decls: {$ifdef VER2_6} TList {$else} { for FPC > 2.6.0 } TFPList {$endif};
begin
  E := TSimpleEngine.Create;
  try
    M := ParseSource(E, ParamStr(1), 'linux', 'i386');

    { Cool, we successfully parsed the module.
      Now output some info about it. }
    if M.InterfaceSection <> nil then
    begin
      Decls := M.InterfaceSection.Declarations;
      for I := 0 to Decls.Count - 1 do
        Writeln('Interface item ', I, ': ' +
          (TObject(Decls[I]) as TPasElement).Name);
    end else
      Writeln('No interface section --- this is not a unit, this is a ', M.ClassName);

    if M.ImplementationSection <> nil then // may be nil in case of a simple program
    begin
      Decls := M.ImplementationSection.Declarations;
      for I := 0 to Decls.Count - 1 do
        Writeln('Implementation item ', I, ': ' +
          (TObject(Decls[I]) as TPasElement).Name);
    end;

    FreeAndNil(M);
  finally FreeAndNil(E) end;
end.

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