Jump to content

Recommended Posts

Variables should always be declared in the smallest scope possible in any language (for languages that support it). For example, don't front-load your functions with all the variable declarations. Declare variables right before they are used. If a variable doesn't need to exist in global scope then use it in local scope. Prefer function return values and function parameters to pass data around rather than global variables. Keep variables in existence no more than necessary.

Link to post
Share on other sites

Contradictory to the UDF standards! But I presume that is more for readability, and writing more structured code.

All variables must be declared at the beginning of the UDF with a “Local” scope and before they are used for the first time.

Also, my original question was one of lots of locals vs. a few globals. With a GUI in message loop mode, the local variables will have to exist until the GUI is closed. With OnEvent mode, the same will apply to a few globals. Given what you have just said, message-loop mode should be used in preference to OnEvent due to the use of locals rather than globals.

Link to post
Share on other sites

Contradictory to the UDF standards! But I presume that is more for readability, and writing more structured code.

I didn't write that nor have I wrote very many UDFs. I do not agree with a lot of things the UDFs do.

Also, my original question was one of lots of locals vs. a few globals. With a GUI in message loop mode, the local variables will have to exist until the GUI is closed. With OnEvent mode, the same will apply to a few globals. Given what you have just said, message-loop mode should be used in preference to OnEvent due to the use of locals rather than globals.

You do not understand what I am saying if you think that. You're seemingly looking for some blanket rule to apply in all situations. That rule does not exist. Whether you use events or a message loop is up to you and the needs of the application you are writing. My statements apply for either mode because my statements are not related to any mode (in fact my statements aren't related to any language in particular, either).
Link to post
Share on other sites

You do not understand what I am saying if you think that. You're seemingly looking for some blanket rule to apply in all situations. That rule does not exist. Whether you use events or a message loop is up to you and the needs of the application you are writing. My statements apply for either mode because my statements are not related to any mode (in fact my statements aren't related to any language in particular, either).

Ok, that sort of answers it anyway. I will contend the fact that the scopes are related to the mode. Message-loops need lots of variables within a single function and OnEvent requires no variables, but in reality you will need to use a few globals for the parent window etc. Granted they can exist in either, and it's fairly trivial anyhow, but i'm fairly sure you'll agree with me on that point.

Link to post
Share on other sites
  • Moderators

Valik,

Thank you for taking the time to post so often in this topic. As a mere hobbyist coder I have found it most interesting to hear the views of a serious programmer and I shall certainly bear your points in mind when I start my next project.

M23

Public_Domain.png.2d871819fcb9957cf44f4514551a2935.png Any of my own code posted anywhere on the forum is available for use by others without any restriction of any kind

Open spoiler to see my UDFs:

Spoiler

ArrayMultiColSort ---- Sort arrays on multiple columns
ChooseFileFolder ---- Single and multiple selections from specified path treeview listing
Date_Time_Convert -- Easily convert date/time formats, including the language used
ExtMsgBox --------- A highly customisable replacement for MsgBox
GUIExtender -------- Extend and retract multiple sections within a GUI
GUIFrame ---------- Subdivide GUIs into many adjustable frames
GUIListViewEx ------- Insert, delete, move, drag, sort, edit and colour ListView items
GUITreeViewEx ------ Check/clear parent and child checkboxes in a TreeView
Marquee ----------- Scrolling tickertape GUIs
NoFocusLines ------- Remove the dotted focus lines from buttons, sliders, radios and checkboxes
Notify ------------- Small notifications on the edge of the display
Scrollbars ----------Automatically sized scrollbars with a single command
StringSize ---------- Automatically size controls to fit text
Toast -------------- Small GUIs which pop out of the notification area

 

Link to post
Share on other sites
  • 3 weeks later...

This topic has been very educational. I am also a mere hobbyist who likes learning these kind of "undocumented" things. Its now got me wondering, are global constants just as bad? I'm telling myself no because there is a ton when it comes to the udfs, but I dont know.

Edit: Looking back, I think this was the dumbest question I have ever asked. :mellow:

Edited by Beege
Link to post
Share on other sites
  • 4 months later...

I just have a question about form. With all due respect to previous posters, I am curious about declaring global variables within a UDF.

For example:

; start program
#include block
GlobalInit()
; rest of code

; end of code

; begin user defined functions
Function GlobalInit()
  Global $a
  Global $b
  Global $c
End Func

Would this be considered bad form from a programming point of view?

Or would it just be bad programming?

Edited by Blue_Drache

Lofting the cyberwinds on teknoleather wings, I am...The Blue Drache

Link to post
Share on other sites
whatever Edited by MvGulik

"Straight_and_Crooked_Thinking" : A "classic guide to ferreting out untruths, half-truths, and other distortions of facts in political and social discussions."
"The Secrets of Quantum Physics" : New and excellent 2 part documentary on Quantum Physics by Jim Al-Khalili. (Dec 2014)

"Believing what you know ain't so" ...

Knock Knock ...
 

Link to post
Share on other sites
  • Moderators

Blue_Drache,

Declaring Global variables in a UDF is something to avoid if you can - but it is often unavoidable. ;)

I just declare them at the beginning of the UDF, making sure I use a unique name to prevent accidental overwriting by the user.

I would certainly not do what you suggest. Why call a function - just declare the variables as normal. Remember that #include inserts the text of the named file at that point in your script, so you would get something like this:

; Your_UDF.au3

Global $a, $b, $c
; followed by UDF code

; ----------------

; Your script

#include "Your_UDF.au3"
; followed by your script code

; ----------------

; Which when expanded will give you 

Global $a, $b, $c
; followed by UDF code
; followed by your script code

Your Global variables are now declared at the beginning of your script as you would wish. :blink:

M23

Public_Domain.png.2d871819fcb9957cf44f4514551a2935.png Any of my own code posted anywhere on the forum is available for use by others without any restriction of any kind

Open spoiler to see my UDFs:

Spoiler

ArrayMultiColSort ---- Sort arrays on multiple columns
ChooseFileFolder ---- Single and multiple selections from specified path treeview listing
Date_Time_Convert -- Easily convert date/time formats, including the language used
ExtMsgBox --------- A highly customisable replacement for MsgBox
GUIExtender -------- Extend and retract multiple sections within a GUI
GUIFrame ---------- Subdivide GUIs into many adjustable frames
GUIListViewEx ------- Insert, delete, move, drag, sort, edit and colour ListView items
GUITreeViewEx ------ Check/clear parent and child checkboxes in a TreeView
Marquee ----------- Scrolling tickertape GUIs
NoFocusLines ------- Remove the dotted focus lines from buttons, sliders, radios and checkboxes
Notify ------------- Small notifications on the edge of the display
Scrollbars ----------Automatically sized scrollbars with a single command
StringSize ---------- Automatically size controls to fit text
Toast -------------- Small GUIs which pop out of the notification area

 

Link to post
Share on other sites

Then it is "Bad programming". I was looking for a more elegant appearing solution than an include file, honestly. Thank you though. *smacks forehead* #Region is exactly what I needed. Sorry to have bothered.

*wanders off muttering about how handy help files can be*

Edited by Blue_Drache

Lofting the cyberwinds on teknoleather wings, I am...The Blue Drache

Link to post
Share on other sites
  • 4 years later...

Nice reading.

Signature beginning:
Please remember: "AutoIt"..... *  Wondering who uses AutoIt and what it can be used for ? * Forum Rules *
ADO.au3 UDF * POP3.au3 UDF * XML.au3 UDF * IE on Windows 11 for other useful stuff click the following button:

Spoiler

Any of my own code posted anywhere on the forum is available for use by others without any restriction of any kind. 

My contribution (my own projects): * Debenu Quick PDF Library - UDF * Debenu PDF Viewer SDK - UDF * Acrobat Reader - ActiveX Viewer * UDF for PDFCreator v1.x.x * XZip - UDF * AppCompatFlags UDF * CrowdinAPI UDF * _WinMergeCompare2Files() * _JavaExceptionAdd() * _IsBeta() * Writing DPI Awareness App - workaround * _AutoIt_RequiredVersion() * Chilkatsoft.au3 UDF * TeamViewer.au3 UDF * JavaManagement UDF * VIES over SOAP * WinSCP UDF * GHAPI UDF - modest begining - comunication with GitHub REST APIErrorLog.au3 UDF - A logging Library * Include Dependency Tree (Tool for analyzing script relations) *

My contribution to others projects or UDF based on  others projects: * _sql.au3 UDF  * POP3.au3 UDF *  RTF Printer - UDF * XML.au3 UDF * ADO.au3 UDF SMTP Mailer UDF * Dual Monitor resolution detection * * 2GUI on Dual Monitor System * _SciLexer.au3 UDF * SciTE - Lexer for console pane

Useful links: * Forum Rules * Forum etiquette *  Forum Information and FAQs * How to post code on the forum * AutoIt Online Documentation * AutoIt Online Beta Documentation * SciTE4AutoIt3 getting started * Convert text blocks to AutoIt code * Games made in Autoit * Programming related sites * Polish AutoIt Tutorial * DllCall Code Generator * 

Wiki: Expand your knowledge - AutoIt Wiki * Collection of User Defined Functions * How to use HelpFile * Good coding practices in AutoIt * 

OpenOffice/LibreOffice/XLS Related: WriterDemo.au3 * XLS/MDB from scratch with ADOX

IE Related:  * How to use IE.au3  UDF with  AutoIt v3.3.14.x * Why isn't Autoit able to click a Javascript Dialog? * Clicking javascript button with no ID * IE document >> save as MHT file * IETab Switcher (by LarsJ ) * HTML Entities * _IEquerySelectorAll() (by uncommon) * IE in TaskSchedulerIE Embedded Control Versioning (use IE9+ and HTML5 in a GUI) * PDF Related:How to get reference to PDF object embeded in IE * IE on Windows 11

I encourage you to read: * Global Vars * Best Coding Practices * Please explain code used in Help file for several File functions * OOP-like approach in AutoIt * UDF-Spec Questions *  EXAMPLE: How To Catch ConsoleWrite() output to a file or to CMD *

I also encourage you to check awesome @trancexx code:  * Create COM objects from modules without any demand on user to register anything. * Another COM object registering stuffOnHungApp handlerAvoid "AutoIt Error" message box in unknown errors  * HTML editor

winhttp.au3 related : * https://www.autoitscript.com/forum/topic/206771-winhttpau3-download-problem-youre-speaking-plain-http-to-an-ssl-enabled-server-port/

"Homo sum; humani nil a me alienum puto" - Publius Terentius Afer
"Program are meant to be read by humans and only incidentally for computers and execute" - Donald Knuth, "The Art of Computer Programming"
:naughty:  :ranting:, be  :) and       \\//_.

Anticipating Errors :  "Any program that accepts data from a user must include code to validate that data before sending it to the data store. You cannot rely on the data store, ...., or even your programming language to notify you of problems. You must check every byte entered by your users, making sure that data is the correct type for its field and that required fields are not empty."

Signature last update: 2022-03-07

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...