Foreach loop for AutoHotkey v2.

[vasili111]

Currently AutoHotkey has several loops that in fact are functioning as Foreach loop. So AutoHotkey has these loops that are functioning like Foreach loop:

1. For - is used for arrays and objects.
2. LoopReg or Loop, Reg - for registry.
3. LoopFiles or Loop, Files - for files and folders.
4. Loop, read - for each lines in text file.
5. LoopParse or Loop, Parse - for substrings (fields) from a string.

Each of above 5 commands are in fact Foreach loops but they have different names. So 5 different commands that in fact are functioning as one Foreach command. I think it is misleading.
In some cases we use Loop loop as Foreach loop. Autohotkey also uses Loop as While loop. So we are using one loop as two kind of loops and it is misleading.
In some cases we use For loops as Foreach loop. It is also misleading because many programming languages are using For loop as For loop (JavaScript, C++).

I propose to use only Foreach loop instead of all these loops. So, it will look like:

1. Foreach, key - is used for arrays and objects.
2. Foreach, subkey - for registry.
3. Foreach, ff - for files and folders.
4. Foreach, line - for each lines in text file.
5. Foreach, substring - for substrings (fields) from a string.

I think it will be more intuitive and right way to use one Foreach loop instead of all different loops that are currently functioning as Foreach loop.

[nnnik]

Or rather:

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For each,RegestryKey in GetRegKeys()
For each,File in GetFiles(Pattern)
For each,Line in StringSplit(InputFile,["`r","`n","`r`n"])
For each, Str in StringSplit(InputString,delimiters)

[vasili111]

nnnik
In AutoHotkey as far as I know all commands consist of one word (except else if) and I think we need to stick to that rule. So I think Foreach is better or it can be written as ForEach.

[nnnik]

Well you dont have to write For each.
You can write For FileName,File in FileObjlist.

[vasili111]

You can write For FileName,File in FileObjlist.

Please, write exactly what you mean should be written. You mean using For instead of Foreach?

[toralf]

That's what i understand. Basically "each" becomes then the same as "A_Index"

[fincs]

Now that we've opened this can of worms, here's my suggestion:

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for file in Files("Path" [, "F|D|R"]) ; file is an object (with dynamically calculated properties like RegExMatch objects): file.fullPath, file.extension, etc etc
for key in RegKeys("RootKey\Key" [, "V|K|R"]) ; as above. e.g. key.subKey, key.type, etc etc
for field in StrFields(string [, delimiters, omitChars]) ; field is a string
for line in FileLines(fileName) ; line is a string

Renaming 'for' to 'foreach' is IMO extremely pointless and more verbose.

[vasili111]

That's what i understand. Basically "each" becomes then the same as "A_Index"

No. Currently we have For , LoopReg or Loop, Reg , LoopFiles or Loop, Files , Loop, read , LoopParse or Loop, Parse and I suggested to make instead of all these loops one Foreach loop.

[guest3456]

Can of worms indeed. Why is this needed?

Simply because some of the Loop constructs can be 'thought of' as "foreach"? Every for/while/loop structure is always going to be a "foreach". Thats what loops do. They iterate over items.

Even a normal loop like this could be considered a "foreach":

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Loop, 10
   msgbox, loop number %a_index%

"Foreach loop#, display message box showing loop #"

But the word "Loop" is far more intuitive for almost every person compared to "for" or "foreach". Anyway, if the sole purpose of this change is a subjective account of what is more "intuitive", seems like its wholly unnecessary

AHKv2 aims to break compatibility, but soon you will be requesting to change everything so much that it will no longer even look like AHK. This is a waste of dev time

[toralf]

Fincs, what would be the difference between your strfields() and strsplit()?

I assume filelines() returns basically an array of lines created by FileReadLine, right?

But I agree with guest3456. Unless there is an additional benefit which currently do not see

[fincs]

None of the functions I proposed in my earlier post would pre-calculate the entries that would be iterated over, instead the enumerator would compute them on demand.

[guest3456]

nnnik
In AutoHotkey as far as I know all commands consist of one word (except else if) and I think we need to stick to that rule. So I think Foreach is better or it can be written as ForEach.

Well you dont have to write For each.
You can write For FileName,File in FileObjlist.

Please, write exactly what you mean should be written. You mean using For instead of Foreach?

You don't understand.

That's what i understand. Basically "each" becomes then the same as "A_Index"

No. Currently we have For , LoopReg or Loop, Reg , LoopFiles or Loop, Files , Loop, read , LoopParse or Loop, Parse and I suggested to make instead of all these loops one Foreach loop.

And he is saying, why make all of these into "foreach" when they can already be done with "for"?

What you are proposing is already possible using the current syntax by simply naming your variables, or creating your own functions to return an object to use in the for loop.

This is working AHK v1.1 code:

Loop:

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Loop, 5
   msgbox, loop number %A_Index%
   
for each in [1,2,3,4,5]
   msgbox, for iteration %each%

Loop, Parse

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string := "red,blue,green"

Loop, Parse, string, `,
   msgbox, % "loop parse: " . A_loopField

for each, field in StrSplit(string, ",")
   msgbox, % "for: " . field

Loop, Files

Code: Select all

Loop, %A_ScriptDir%\*.*
   msgbox, % "loop files:`n`n" . A_LoopFileName

for each, file in GetFiles(A_ScriptDir)
   msgbox, % "for:`n`n" . file
   
GetFiles(dir)
{
   array := []
   Loop, %dir%\*.*
      array.Insert(A_LoopFileName)
   return array
}

You will note that using the variable name "each" for the object keys is completely arbitrary and irrelevant in these exmaples, but simply done because you like the sound of it

[lexikos]

Each of above 5 commands are in fact Foreach loops but they have different names. So 5 different commands that in fact are functioning as one Foreach command. I think it is misleading.

I laughed out loud when I read this. Please explain to me how this "misleads" users and how that actually matters.

For/foreach is really just a conditional jump combined with a few method calls:

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_enum := (Expression)._NewEnum()
if IsObject(_enum)
    while _enum.Next(Key, Value)
    {
        ...
    }

(Straight from the manual.) I think it is "misleading" and therefore propose that we do away with for loops and just use if and while. Or perhaps we should do away with while and just use if and goto.

Does anyone else think that "Loop" is easier for beginners to grasp?

Autohotkey also uses Loop as While loop. So we are using one loop as two kind of loops and it is misleading.

Does not. There's a separate command for While loops. Loop Count is equivalent to for (A_Index = 1; A_Index <= Count; ++A_Index), not foreach. AutoHotkey uses "Loop" for several types of loops, because they are loops. Perhaps it should use "Loop" for for-loops and while-loops as well (and I think IronAHK went that way), but I thought it was too verbose.

In some cases we use For loops as Foreach loop. It is also misleading because many programming languages are using For loop as For loop (JavaScript, C++).

AutoHotkey's for loop is modelled after JavaScript's for..in loop. How is it misleading when they have the same name and virtually the same behaviour? AutoHotkey's for loop is even compatible with JavaScript objects.

The Loop commands are not functioning as foreach loops. There is no collection object being enumerated, no enumerator object, and therefore no Next() call on each iteration.

In AutoHotkey as far as I know all commands consist of one word (except else if)

There is no "else if" command or statement; it is two separate statements. But there is "for in", "Loop Parse", "Loop Files", etc. and there was "if x between y and z", "if is", "if in" and "if contains".


guest3456: For once, I agree with you.

[nnnik]

@guest3456 exactly what I meant.

[TWATS]

What a confusing mess. The documentation needs to explain the pattern of for loops simply.

[lmstearn]

Curious that in 11.24.03:

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string := "red,blue,green"
  for each, field in StrSplit(string, ",")
   msgbox, % "for: " . field

compiles the same as

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string := "red,blue,green"
for whateverstringisputinheretheresultisthesame, field in StrSplit(string, ",")
   msgbox, % "for: " . field

[guest3456]

Curious that in 11.24.03:

Code: Select all

string := "red,blue,green"
  for each field in StrSplit(string, ",")
   msgbox, % "for: " . field

compiles the same as

Code: Select all

string := "red,blue,green"
for whateverstringisputinheretheresultisthesame, field in StrSplit(string, ",")
   msgbox, % "for: " . field

nothing curious about it:
https://autohotkey.com/docs/commands/For.htm

[lmstearn]

Aha:

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for fearofpostingsomethingalittletooobvious, field in StrSplit(string, ",")
   msgbox, %  "fearofpostingsomethingalittletooobvious: " fearofpostingsomethingalittletooobvious " for: " . field

fearofpostingsomethingalittletooobvious is the key!

If key is removed, what happens now?

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string := "red,blue,green"
  
for , field in StrSplit(string, ",")
   msgbox, %  " for: " . field

[guest3456]

If key is removed, what happens now?

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string := "red,blue,green"
  
for , field in StrSplit(string, ",")
   msgbox, %  " for: " . field

what do you think happens? did you run your code?

key is not in [brackets] so its a required parameter. its not allowed to be missing. read the help page.
https://autohotkey.com/docs/commands/For.htm

your code is the same as msgbox , param1
command, then optional comma, then first parameter