The place for the VB community to join our collective voice! See https://github.com/CommunityVB/Main for more info.
AND... what if... and I do ask this in all seriousness... this were possible WITHOUT changing the VB compiler? It might just indeed be possible to support this with the tools that currently exist where (once available) all you would have to do is simply add a nuget reference.
Which then leads me to ask what would PRINT (or ?) do for different project types? In a Console application it would output text to the, well, Console. In a WinForms application, would it be equivalent to a Debug.Print or for "logging"? In an ASP.NET type application, would it be for sending content to the browser (HTML)?
DISCLAIMER: This may be something that requires a team of people to participate in (ultimately) to accomplish.
I'm in the process of learning more about Roslyn (navigating through syntax trees) and in the process of exploring how I want to handle certain things I discovered that ? is something that is specifically looked for. Just for giggles, tried the following code in a method:
? "HELLO WORLD!"And the error one receives will be similar to "Expression statement is only allowed at the end of an interactive submission."
This statement, though, is completely recognized and parses correctly since it is legal in the interactive side of things and, at least to me, it's interesting to see entry.Kind = SyntaxKind.PrintStatement.
This will make it a little more difficult (in some ways) to do what I'm wanting to do... however, it also makes it easy to detect (since it already can do so).
Point being that ? is does (technically) exist in VB (Roslyn) but is only used (assumption) in limited scope (interactive")... (NOTE: It might not actually be used outside of the error checking, I'm making an assumption that the very limited interactive stuff in VS is using this; it might not be as it could still be using the old way* since we don't have VB scripting available to us.) I may explore this more in the future; but if anyone else knows any more details, please share.
After a long wait my fix to handling formatting _ ‘ is in the current release of Visual Studio 2022. I want the thank @CyrusNajmabadi and @SamHarwell for making it happen. This continues to give me hope to be able at add additional feature to VB by community in the future.
AWESOME!
This continues to give me hope to be able at add additional feature to VB by community in the future.
My view is that the answer has (all along) not been a (hard) "No!"... but rather the bar is pretty high in order to get a "Yes!". Also, "no plan" doesn't mean "nothing is going to happen"; or, more specifically, plans can and do change over the course of time. Changes are indeed taking place both within Roslyn as well as in .NET / Visual Studio / WinForms / etc. that DIRECTLY impact VB.
to answer your question about VB, I'm working on trying to make things more async, and to work on perf not causing blocking issues in it in the typing experience -- @CyrusNajmabadi
Can you take a moment to update about the work you were referring to when you posted this a while back?
? for printing, even if it possible. In C#, we use cw+tab shortcut for Console.writeline snippent, which doesn't exist in VB, and there is an issue about that dotnet/roslyn#37049
<?xml version="1.0" encoding="utf-8"?>
<CodeSnippets xmlns="http://schemas.microsoft.com/VisualStudio/2005/CodeSnippet">
<CodeSnippet Format="1.0.0">
<Header>
<Title>Console.WriteLine</Title>
<Author>M. Hmdy Ghanem</Author>
<Shortcut>cw</Shortcut>
</Header>
<Snippet>
<Code Language="VB">
<![CDATA[Console.WriteLine($msg$)]]>
</Code>
<Declarations>
<Object>
<ID>msg</ID>
<Type>System.String</Type>
<ToolTip>The message you want to write.</ToolTip>
<Default>"Hello"</Default>
</Object>
</Declarations>
</Snippet>
</CodeSnippet>
</CodeSnippets>https://docs.microsoft.com/en-us/visualstudio/ide/walkthrough-creating-a-code-snippet?view=vs-2022
Console.WriteLine("Hello")The "Hello" text will be highlighted so you can replace it.
? as a shortcut for the snippet, but didn't work as it is used to show the snippet context menu. It would be nice ;)
cwl.
@CyrusNajmabadi
Does the visual basic specification and compiler, assert atomicity within "multi-part" block structures.
For example the ElseIf in an If Then ... End If block.
We have the following code (as is).
' statements 0
If someCondition = True Then
' statements 1
ElseIf someCondition = False Then
' statements 2
Else
' statements 3
End If
' statements 4is transformed into
' statements 0
If someCondition = True Then
' statements 1
Else
' *** What prevents evaluate of someCondition being different from prior evaluation.
If someCondition = False Then
' statements 2
Else
' statements 3
End If
End If
' statements 4Is someCondition asserted to be atomic ( non-changing ) between each usage?
As from my knowledge the lowered form does not seem to have that "ambient property", or does the transformation production obtain that "ambient property" from the transformation of an ElseIf statement.
If it doesn't would a copy of the value of "someConditon" into "tmp" prior to the If Block, and rename the usage of "someCondition" with on this block to "tmp". Gain that guarentee.
I think this is something to do with Side-Effects and/or Contract propagation.
Otherwise, if the variable you are testing is not a local variable but instead a property of a class... the class could literally return a different result each and every check.
Alternatively (I believe) this could be resolve by using Select Case.
If it doesn't would a copy of the value of "someConditon" into "tmp" prior to the If Block, and rename the usage of "someCondition" with on this block to "tmp". Gain that guarentee.
This would only be true if the developer honored this restriction.
https://blog.trailofbits.com/2019/06/27/use-constexpr-for-faster-smaller-and-safer-code/
is predominantly is lowered to anIf ... Then` structure, so same suitable effect exists. In a "pure" single threaded non-eventing/interuptting evaluation it trivial and can be ignored. In a non-linear evaluation environment it does, so assisting the programmer to have awareness, or code-fix.
If checking is completely within the context of the If statements. So multi-threaded code shouldn't be an issue (in this example - which I feel is more common). In the event the value does change, there is a high possibility this was what the developer desired/intended. Now if we talk about properties... the value of the property is controlled by the object and one would have to wonder under what conditions that this would be an issue. In some circumstances, the value changing between the If statements may actually be desired. There are also two very different Select Case models (lowering)... as you said there is one that is basically a bunch of individual If statements while the (ultimately) desired lowering would be the "jump list". To my knowledge, the "jump list" version would evaluate the value once and is significantly faster than and something I tend to try to setup for under normal conditions. If the desire is to make the variable unchanging, there are (of course) mechanisms in place to assist with that as well. But I don't think there is a "blanket" mechanism or even warning that would cover all the scenarios and my gut is telling me this would create more confusion than it would potentially address any sort of pitfall. In other words, I can't imagine how one would look at the code a know whether or not this might be a potential issue across all the possible scenarios that could exist. I could, of course, be missing something... so there is always that. ;-)
and is a code fix possible?
Of course it would be better if intellisense take snippets shortcuts into account.
A nice surprise: @sharwell pointed out that there is an option to trun on this feature!
https://github.com/dotnet/roslyn/issues/37049#issuecomment-998997945
something, otherthing) are to be treated as having a single immutable value (or the "value" will not be altered.). Is there enough evidence to support or proof that statement, from the specification.