What is the benefit of sorting the Uses clause?

[RCrandall 8]

I am returning to MMX after a long break and I'm exploring it all again.  I dimly recall seeing that the order of the Uses clauses can affect compilation speed, a problem I'm having, but I'm far from sure of that.  Is this the benefit of formatting the list of used units?  Or is to improve readability, or some other reason?

 

Inquiring minds want to know, thanks, Rob C

[Uwe Raabe 2064]

It started with the request to expand the unit scope names, which gave a good boost to compile time in some cases. The idea of uses clause grouping and sorting crept in my mind when I noticed difficulties to quickly scan the list of used units. With a sorted and grouped uses clause the used libraries are clearly visible immediately. So its partly for compilation speed as well as a neat look (some call it OCD).

[Fred Ahrens 59]

Sorting units by name is dangerous.

There are some units that need to be added at the end of the list, if they overwrite some behavior's of objects and functions of other units above in the list. There are other units that need to be placed on top of the list if they do some special initialization that needs to be done in the app as soon as possible, before any other parts of the app start to initialize.

[Uwe Raabe 2064]

43 minutes ago, Fred Ahrens said:

Sorting units by name is dangerous.

Albeit there actually is a request for that, MMX does not sort the units by name. They are grouped according to a user defined pattern, but inside the group the order stays intact.

 

F.i. this is the Groups entry for one of my projects: 

 

After some Delphi units in a decent order based on dependency, there are the Raize and TMS units followed by VirtualTrees, PngComponents and the ZipForge units. The last four mimic the unit scopes and naming convention of the project itself also ordered by dependency.

(TMS can improve their unit naming btw.)

 

A typical uses clause looks like this:

uses
  Winapi.Messages,
  System.Classes, System.Actions, System.Types, System.ImageList,
  Vcl.Graphics, Vcl.Menus, Vcl.ActnList, Vcl.Controls, Vcl.ExtCtrls, Vcl.Forms, Vcl.StdCtrls, Vcl.Tabs, Vcl.Dialogs, Vcl.ImgList,
  Vcl.VirtualImageList, Vcl.AppEvnts,
  RzTabs, RzForms, RzShellDialogs, RzPanel, RzButton, RzSplit, RzCommon,
  Common.Form,
  IpButton, IpMRU, IpMultiLanguageSupport,
  TcEditorTypes, TcGlbCfgSystem, TcGlbCfgVisualStyle,
  RNcCodeViewer, REditorStructure, REditorItems, RBasePalette, RStoragePalette, REditorPalette, RCustomPalette, REditorPanel,
  RBaseFrame, RObserver, RStandardStatus, REditorNesting, RBaseEditorFrame;

 

The grouping algorithm is pretty flexible and I never had a case that could not be handled.

 

If auto-sort a uses clause is automatically sorted whenever MMX modifies it - a very handy feature.

[mvanrijnen 123]

2 hours ago, Fred Ahrens said:

Sorting units by name is dangerous.

There are some units that need to be added at the end of the list, if they overwrite some behavior's of objects and functions of other units above in the list. There are other units that need to be placed on top of the list if they do some special initialization that needs to be done in the app as soon as possible, before any other parts of the app start to initialize.

Actually this means there is a design flaw (i know, hard to not have this situations, we have them also, but in reallity it's something to fix i think).

How you going explain 15years later that unit xyz has to be before unit abc, put some text in comments ?

 

[David Heffernan 2353]

9 hours ago, Fred Ahrens said:

Sorting units by name is dangerous.

There are some units that need to be added at the end of the list, if they overwrite some behavior's of objects and functions of other units above in the list. There are other units that need to be placed on top of the list if they do some special initialization that needs to be done in the app as soon as possible, before any other parts of the app start to initialize.

Although the real problem is the language design that makes this order affect the meaning of the program. 

[Lars Fosdal 1793]

I remember having this discussion with an american on LinkedIn. He had written a tool that sorted the uses clause, and he turned a darker shade of crazy when I pointed out the risks, "chanting" USA, USA, USA. No point in discussing with such people.

[RCrandall 8]

18 hours ago, Uwe Raabe said:

It started with the request to expand the unit scope names, which gave a good boost to compile time in some cases. The idea of uses clause grouping and sorting crept in my mind when I noticed difficulties to quickly scan the list of used units. With a sorted and grouped uses clause the used libraries are clearly visible immediately. So its partly for compilation speed as well as a neat look (some call it OCD).

"Expand unit scope names" - that was it. Thanks for the speedy reply and I appreciate all the other comments too.

 

Rob C

[Rollo62 539]

9 hours ago, Lars Fosdal said:

... "chanting" USA, USA, USA. No point in discussing with such people.

Probably you misunderstood him a little, since this was his desired (world) sort order ... 🤔

[Attila Kovacs 631]

Make te uses list great again!

[Fr0sT.Brutal 900]

On 9/1/2023 at 2:39 AM, mvanrijnen said:

Actually this means there is a design flaw

RTL itself suffers from this flaw for some identifiers (mostly WinAPI / generic types clash). Luckily these issues are detected by compiler but could cause serious issues if these types are used as untyped pointers

 

[JonRobertson 72]

On 8/31/2023 at 5:00 PM, Uwe Raabe said:

How do you configure groups like (ZipForge)? I could not find that in MMX Properties or MMX Project Options.

 

I would like to do this for ImageEn and maybe others. ImageEn units do not have a consistent prefix suitable for grouping.

 

Thanks!

 

Thanks

[Uwe Raabe 2064]

Brackets denote a list of unit names forming a group. I use it f.i. for keeping the ToolsApi units together: (ToolsApi,DesignIntf,DCCStrs,DockForm,TabDock)

 

The example shows a glitch in the TMS unit naming: Adv* followed by (BaseGrid) keeps the TMS Grids unit together.

 

The other example (ZipForge) is used when a group consists of a single unit name only. Omitting the brackets would take it as a unit scope name instead.

 

 

[ULIK 16]

Uwe,

 

where do I find this groups dialog? Is this a new feature you are working on?  

Found it!

 

Thanks!

 

Edited November 23, 2023 by ULIK

[haentschman 92]

@Uwe Raabe

Hi...😎

 

Is it possible to start each group in a new line?

uses
  Winapi.Windows,
  System.Classes, System.Generics.Collections, System.Generics.Defaults, System.SysUtils,
  ...

 

[Uwe Raabe 2064]

26 minutes ago, haentschman said:

Is it possible to start each group in a new line?

That's default.

[haentschman 92]

...🤔

before:

uses
  System.Classes, System.SysUtils, System.Variants, System.Generics.Collections, System.Generics.Defaults, System.DateUtils, System.Math, System.StrUtils,
  Vcl.Imaging.pngimage,
  Data.DB,
  FireDAC.Stan.Param, FireDAC.Stan.Option, FireDAC.Comp.Client, FireDAC.Comp.Script,
  DataModuleTextConstants,
  x.Classes.Common, x.Classes.Base, x.Classes.Data, x.Constants, x.Types,
  x.Tools.Mapping, x.Tools.DateTime, x.Tools.TryFinally, x.Tools.Json, x.Tools.Regex, x.Tools.IO, x.Tools.BitMask,
  x.Database.Common,
  x.Preferences;

after:

uses
  System.Classes, System.SysUtils, System.Variants, System.Generics.Collections, System.Generics.Defaults, System.DateUtils, System.Math,
  System.StrUtils, Vcl.Imaging.pngimage, Data.DB, FireDAC.Stan.Param, FireDAC.Stan.Option, FireDAC.Comp.Client, FireDAC.Comp.Script,
  DataModuleTextConstants, x.Classes.Common, x.Classes.Base, x.Classes.Data, x.Constants, x.Types, x.Tools.Mapping,
  x.Tools.DateTime, x.Tools.TryFinally, x.Tools.Json, x.Tools.Regex, x.Tools.IO, x.Tools.BitMask, x.Database.Common,
  x.Preferences;

[Uwe Raabe 2064]

And for completeness: What are the defined groups?

[haentschman 92]

Sorry...😉

PS: with "*" ("Form.*") also...  

PS: FireDAC and more are missing (first test)  😉

 

Edited November 23, 2023 by haentschman

[Stano 143]

I have: Winapi;System.Win;System;Data;Vcl;obsidium;Adv*;(BaseGrid);Virtual*;FireDAC;REST;Xml;fcx*;VclTee;jst*;Vst*;sub*;u*

Result:

uses
  Winapi.Windows, Winapi.Messages,
  System.SysUtils, System.Variants, System.Classes, System.Generics.Collections, System.Generics.Defaults,
  System.DateUtils,
  Data.DB,
  Vcl.Graphics, Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.ExtCtrls, Vcl.StdCtrls,
  advofficepager, AdvMemo, advglowbutton, advpanel, advstyleif, advappstyler,
  FireDAC.Comp.Client, FireDAC.Stan.Param,
  jstAdvPanel,
  BasalForm, Htmlabel;

[Uwe Raabe 2064]

Better remove the trailing dots in Frame and Form. Plain group names get that automatically appended when looking for a match.

 

F.i. a simple entry like Form matches unit names Form, Form.Tools and Form.Test, but not FormTest.

 

Assuming that the x stands for the obfuscated parts in your screenshot, I get the following results with this Groups: 

Winapi
System.Win
System
Vcl
Data
FireDAC
cx
DM
x
x.Tools
Frame
Form

uses
  System.Classes, System.SysUtils, System.Variants, System.Generics.Collections, System.Generics.Defaults, System.DateUtils,
  System.Math, System.StrUtils,
  Vcl.Imaging.pngimage,
  Data.DB,
  FireDAC.Stan.Param, FireDAC.Stan.Option, FireDAC.Comp.Client, FireDAC.Comp.Script,
  x.Classes.Common, x.Classes.Base, x.Classes.Data, x.Constants, x.Types, x.Database.Common, x.Preferences,
  x.Tools.Mapping, x.Tools.DateTime, x.Tools.TryFinally, x.Tools.Json, x.Tools.Regex, x.Tools.IO, x.Tools.BitMask,
  DataModuleTextConstants;

 

[Attila Kovacs 631]

Each unit name belongs to a new line, with groups separated by an empty line.

[Uwe Raabe 2064]

11 minutes ago, Attila Kovacs said:

Each unit name belongs to a new line, with groups separated by an empty line.

As that is a very personal preference, a similar feature is implemented on personal request in UsesCleaner branch FlixEngineering. It is available in the public repository for all those having individual formatting requests.

 

Note that MMX will most likely not contain these for the near future.

[dummzeuch 1517]

3 hours ago, Attila Kovacs said:

Each unit name belongs to a new line, with groups separated by an empty line.

Actually, instead of an empty line, it could be a comment with the group, e.g.

uses
  // Windows group
  Windows.WinApi
  // vcl group
  vcl.bla,
  vcl.blub;

So it doesn't look like somebody forgot to remove an empty line.

Edited November 23, 2023 by dummzeuch

[haentschman 92]

😢 I put this in the groups...

Quote

Winapi
System.Win
System
Vcl
Data
FireDAC
cx
DM
x
x.Tools
Frame
Form

 

after:

uses
  System.Classes, System.SysUtils, System.Variants, System.Generics.Collections, System.Generics.Defaults, System.DateUtils, System.Math,
  System.StrUtils, Vcl.Imaging.pngimage, Data.DB, FireDAC.Stan.Param, FireDAC.Stan.Option, FireDAC.Comp.Client, FireDAC.Comp.Script,
  DataModuleTextConstants, x.Classes.Common, x.Classes.Base, x.Classes.Data, x.Constants, x.Types, x.Tools.Mapping,
  x.Tools.DateTime, x.Tools.TryFinally, x.Tools.Json, x.Tools.Regex, x.Tools.IO, x.Tools.BitMask, x.Database.Common,
  x.Preferences;

What ist wrong?

PS: 15.1.8

Edited November 23, 2023 by haentschman