IDE Window: Extract Procedure/fr

From Lazarus wiki
Revision as of 05:01, 14 July 2007 by Paulatreides (talk | contribs) (New page: {{IDE Window: Extract Procedure}} Abstract: "Extract Procedure" takes some selected pascal statements and creates a new procedure/method from this code. This tool is useful to split big p...)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigationJump to search

Deutsch (de) English (en) español (es) suomi (fi) français (fr) русский (ru) slovenčina (sk) 中文(中国大陆)‎ (zh_CN)

Abstract: "Extract Procedure" takes some selected pascal statements and creates a new procedure/method from this code. This tool is useful to split big procedures or to easily create a new procedure from some code.

Basic example:

procedure DoSomething;
begin
  CallSomething;
end;

Select the line "CallSomething;" and do Extract Proc. A dialog pop ups and you can select the type and name of the procedure to create. For example: procedure, "NewProc". Result:

procedure NewProc;
begin
  CallSomething;
end;

procedure DoSomething;
begin
  NewProc;
end;

You can see, that the new procedure "NewProc" was created with the selection as body and the old code was replaced by a call.

Local Variables and Parameters:
"Extract Proc" scans for used variables and automatically creates the parameter list and local variables. Example:

procedure TForm1.DoSomething(var Erni, Bert: integer);
var
  i: Integer; // Comment
begin
  Erni:=Erni+Bert;
  for i:=Erni to 5 do begin
  |
  end;
end;

Select the for loop and create a new Procedure "NewProc". The local variable i is only used in the selection, so it will be moved to the new procedure. Erni is also used in the remaining code, so it will become a parameter.

Result:

procedure NewProc(const Erni: integer);
var
  i: Integer; // Comment
begin
  for i:=Erni to 5 do begin
  |
  end;
end;

procedure TForm1.DoSomething(var Erni, Bert: integer);
begin
  Erni:=Erni+Bert;
  NewProc(Erni);
end;

You can see "i" was moved to the new procedure (Note: including its comment) and Erni.

Limitations:
Pascal is a very powerful language, so don't expect it will work with every code. Current limits/ToDos:

  • check if selection bounds on statement bounds
  • "with" statements