Syntax Enhancements: If on-the-fly & expression w/ var asgn.

[crackhead]

Hi,
I don't know, if this is already requested, implemented, not implementable due to other syntactical constructs or that ugly and unuseful, that it'll never be wanted
Sorry, I'm new..


1. If "on-the-fly":
something like

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  SetGadgetText(#MyButton, (MyVar > 0) ? "MyVar > 0" : "MyVar <= 0")

like in C, maybe adapted to BASIC-syntax



2. Expressions with variable-assignment:

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  While (MyVar = MyProcedure) > 0
    MessageRequester("", Str(MyVar))
  Wend

3. Short if:
using if - endif seems to be a bit too much for a single command like

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  If Not DoneYet
    MessageRequester("", "Not done yet.")
  EndIf

and

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  If Not DoneYet : MessageRequester("", "Not done yet.") : EndIf

isn't that readable

What about something like

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  If Not DoneYet Then MessageRequester("", "Not done yet.")

and

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  While MyProcedure > 0 Do MessageRequester("", Str(MyVar))

4. Also, how about ForEach with an array?
One could use For with ArraySize,
but couldn't that be implemented internally into ForEach, too?

I hope my requests aren't too dumb,
Thanks.

[netmaestro]

4. Also, how about ForEach with an array?
One could use For with ArraySize,
but couldn't that be implemented internally into ForEach, too?

I like this one.

[#NULL]

1. i would like to have a conditional operator too. see also these threads:
viewtopic.php?f=3&t=28740&start=0&sid=d ... 2991a4f34e
http://forum.purebasic.com/english/view ... 7d8b07d471

2. this was requested from time to time iirc, but i don't think the pb-team will do it. it's C-ish and too ambiguous for PB style.

3. personally i like the : operator and use it often especially for many sequent single-line If-Endifs. i don't like the Then nor leaving off the EndIf. remember you don't have a explicit block syntax á la { and } in PB.

4. i didn't miss that yet, but why not. it would look much simpler for multi-dim arrays instead of many nested For-loops. but then i would still want to specify index identifier to be able to know where i am during the looping.

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Dim arr(3,4,5)

ForEach arr(x,y,z)
  If y = 2
    arr(x,y,z) = 0
  Else
    arr(x,y,z) = 123
  EndIf
Next

[Kaeru Gaman]

If you want C, why don't you use C?


1. this is clearly C syntax. PureBasic is a BASIC language.

Evalution for Expressions is planned.
Boolean( Expr ) will evaluate 1 or 0 depending on Expr to be True or False.

Your example just compresses five lines of code into one for the cost of readability.
the compiled result still needs to be the same ASM to provide same functionality,
so where should be any win in this cryptic mess?


2. this is also C syntax. may I repeat: PureBasic is a BASIC language.

it is not at all possible without introducing an assignment operator devided from the comparison operator.
in BASIC syntax, your example should evaluate the comparison (MyVar = MyProcedure) if it's True.
PureBasic does not support such evaluating expessions yet (see above)


3. the EndIf was introduced into BASIC decades to enable the Then branch to hold a block of code in more than one line.
in older times you had to write all commands of the Then branch into the same Line.
nevertheless, maybe it is possible the implement this additional alternative syntax.


4. why not?
never thought about it, don't think ever need it, but why not?

[crackhead]

I guess there's a difference between syntactical approaches and a whole different language + compiler.

1)
"for the cost of readability"
you can't simply generalize it, also it wouldn't mean one would have to use it.

2)
Ah, right, I didn't think of the possible need of a different operator

3)
yeah, just as an alternative syntax so that you can choose,
since I think, it'd be more readable than such a block

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If a = "he"
  DoThis()
Endif
If y = z
  DoThat()
Endif
If x
  DoSomething()
Endif
If Error
  ClosePlease()
Endif

alternative syntax/1-line-if:

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If a = "he" Then DoThis()
If y = z Then DoThat()
If x Then DoSomething()
If Error Then ClosePlease()

Or formatted:

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If a = "he" Then DoThis()
If y = z    Then DoThat()
If x        Then DoSomething()
If Error    Then ClosePlease()

[ts-soft]

you can use this:

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Macro Then
  :
EndMacro

Define a = 1

If a = 1 Then Debug "True" Then EndIf

[blueznl]

My eyes! My eyes!

[Foz]

I like inline conditionals. At least for when we deal with grammer:

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; n.b. macro to be removed when the actual Boolean function is released.
Macro boolean(_expression_)
  ((_expression_) Or #False)
EndMacro

Procedure.s IIFs(condition, True.s, False.s)
  If condition
    ProcedureReturn True
  Else
    ProcedureReturn False
  EndIf
EndProcedure

a = 1
Debug Str(a) + " Carton" + IIFs(boolean(a = 1), "", "s")

a = 7
Debug Str(a) + " Carton" + IIFs(boolean(a = 1), "", "s")