Does Anybody Else Miss the WITH construct of Visual Basic?
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I can see what they are trying to do - scope the variable to just the code where the result is actually valid:
{
int result;
if (int.TryParse(input, out result))
Console.WriteLine(result);
else
Console.WriteLine("Could not parse input");
}Only it's out of scope in the
elseblock. And that does make some good sense. But it is ugly - I'll get used to it and it should improve reliability in the long term.Sent from my Amstrad PC 1640 Never throw anything away, Griff Bad command or file name. Bad, bad command! Sit! Stay! Staaaay... AntiTwitter: @DalekDave is now a follower!
The scope of
resultisn't just thetrueside of theifstatement. It's everywhere in the parent scope after theifstatement, except for theelseblock. Get some noob writing a 500 line method and you run into that same problem where you're hunting for where the variable is declared.Asking questions is a skill CodeProject Forum Guidelines Google: C# How to debug code Seriously, go read these articles.
Dave Kreskowiak -
Speaking of hunting back through the code, C# 7 gives us this little gem:
if (int.TryParse(input, out int result))
Console.WriteLine(result);
else
Console.WriteLine("Could not parse input");You get to declare variables in the call to TryParse, or any other method that takes
outparameters. I no likey. I would class this as one of C#'s little "you can't handle the truth" constructs. The docs says it makes the code easier to read. I respectfully disagree.Asking questions is a skill CodeProject Forum Guidelines Google: C# How to debug code Seriously, go read these articles.
Dave KreskowiakHi Dave, I, also, find the in-line 'out variable declaration ... and its persistence beyond what my habitual perceptions suggest should be limited scope ... jarring. I think it needs a little more spice to be really useful in creating FUD:
Console.WriteLine($"result: {(int.TryParse(input, out var result) ? result.ToString() : "no")}");
The fact that the in-line 'result variable will persist even in this example ... don't feel right. And, use of 'var in this case seems, intuitively, wrong. But, perhaps these little frissons of cognitive dissonance are just evidence for the old conundrum of 'old dogs cannot learn new tricks' ?
«Where is the Life we have lost in living? Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?» T. S. Elliot
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As I read [Adam Storr - Playing with C# 7 - Deconstruct](https://adamstorr.azurewebsites.net/blog/playing-with-csharp-7-deconstruct?utm\_source=Main&utm\_campaign=0cdc8b3a40-EMAIL\_CAMPAIGN\_2017\_12\_19\_COPY\_01&utm\_medium=email&utm\_term=0\_aa2f642d94-0cdc8b3a40-227561569&mc\_cid=0cdc8b3a40&mc\_eid=8087c9508d), I kept hoping that it would answer at long last the question of how to do
within C#. Alas, it fell short again. Does anybody besides me wish that C# supportedwithblocks, or have I overlooked a seriously underused language feature?David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
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As I read [Adam Storr - Playing with C# 7 - Deconstruct](https://adamstorr.azurewebsites.net/blog/playing-with-csharp-7-deconstruct?utm\_source=Main&utm\_campaign=0cdc8b3a40-EMAIL\_CAMPAIGN\_2017\_12\_19\_COPY\_01&utm\_medium=email&utm\_term=0\_aa2f642d94-0cdc8b3a40-227561569&mc\_cid=0cdc8b3a40&mc\_eid=8087c9508d), I kept hoping that it would answer at long last the question of how to do
within C#. Alas, it fell short again. Does anybody besides me wish that C# supportedwithblocks, or have I overlooked a seriously underused language feature?David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
You really want 'With in C#: [^]. This hack uses reflection ... I'd never use it in production code: [^] And, now, the "sermon:" I think it's a mistake to try and "bend" C# to fit your background in another language. At the same time, imho, most people will, in the first phase of learning, look for, expect, things/structures through mental habits conditioned by other languages. I believe (hypothesis) that programmers often have a kind of imprinting/bonding experience with the first language they learn well. Surrender ! :wtf:
«Where is the Life we have lost in living? Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?» T. S. Elliot
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Hi Dave, I, also, find the in-line 'out variable declaration ... and its persistence beyond what my habitual perceptions suggest should be limited scope ... jarring. I think it needs a little more spice to be really useful in creating FUD:
Console.WriteLine($"result: {(int.TryParse(input, out var result) ? result.ToString() : "no")}");
The fact that the in-line 'result variable will persist even in this example ... don't feel right. And, use of 'var in this case seems, intuitively, wrong. But, perhaps these little frissons of cognitive dissonance are just evidence for the old conundrum of 'old dogs cannot learn new tricks' ?
«Where is the Life we have lost in living? Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?» T. S. Elliot
That code is ..... disturbing. I think about half the new features showing up in C# now are just for syntactic sugar. This is one where I think the community of old-timers would be split on its usefulness vs how many people would actually use it. I'd be interested in seeing any telemetry on its use.
Asking questions is a skill CodeProject Forum Guidelines Google: C# How to debug code Seriously, go read these articles.
Dave Kreskowiak -
You really want 'With in C#: [^]. This hack uses reflection ... I'd never use it in production code: [^] And, now, the "sermon:" I think it's a mistake to try and "bend" C# to fit your background in another language. At the same time, imho, most people will, in the first phase of learning, look for, expect, things/structures through mental habits conditioned by other languages. I believe (hypothesis) that programmers often have a kind of imprinting/bonding experience with the first language they learn well. Surrender ! :wtf:
«Where is the Life we have lost in living? Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?» T. S. Elliot
Did you see my terse example? Do you like typing the class name in front of every member name in a code block that sets ten properties one after another?
David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
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Did you see my terse example? Do you like typing the class name in front of every member name in a code block that sets ten properties one after another?
David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
Did I see the code sample that would never compile [^]: yes. Did I see a reference in another post you made to something "illustrated" without explanation: yes.
David A. Gray wrote:
Do you like typing the class name in front of every member name in a code block that sets ten properties one after another?
I do not see how this "sucker-punch question" is relevant to anything discussed here :) Beginning with the object initializer syntax in C# (C# 3.0, .NET 3.5), initializing a bunch of whatever when a new object was created became much easier. What's your issue here ? If you want to simulate 'With, techniques are well known, for a long time (see my post here). Now, if you have a better way, that doesn't use reflection, or the usual Extension Method: I'm all ears !
«Where is the Life we have lost in living? Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?» T. S. Elliot
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As I read [Adam Storr - Playing with C# 7 - Deconstruct](https://adamstorr.azurewebsites.net/blog/playing-with-csharp-7-deconstruct?utm\_source=Main&utm\_campaign=0cdc8b3a40-EMAIL\_CAMPAIGN\_2017\_12\_19\_COPY\_01&utm\_medium=email&utm\_term=0\_aa2f642d94-0cdc8b3a40-227561569&mc\_cid=0cdc8b3a40&mc\_eid=8087c9508d), I kept hoping that it would answer at long last the question of how to do
within C#. Alas, it fell short again. Does anybody besides me wish that C# supportedwithblocks, or have I overlooked a seriously underused language feature?David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
I'm still doing some programming in VB.Net. I never use With.
Wrong is evil and must be defeated. - Jeff Ello
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You really want 'With in C#: [^]. This hack uses reflection ... I'd never use it in production code: [^] And, now, the "sermon:" I think it's a mistake to try and "bend" C# to fit your background in another language. At the same time, imho, most people will, in the first phase of learning, look for, expect, things/structures through mental habits conditioned by other languages. I believe (hypothesis) that programmers often have a kind of imprinting/bonding experience with the first language they learn well. Surrender ! :wtf:
«Where is the Life we have lost in living? Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?» T. S. Elliot
BillWoodruff wrote:
I think it's a mistake to try and "bend" C# to fit your background in anothr language.
I'd agree - and suspect that's what a lot of the recent C# changes have been driven by: VB and C++ developers which want to continue writing VB and C++ code in C# instead of learning a newer, fresher language paradigm. And maybe that's why C# is getting "bloated" and losing it's focus as a coherent language.
Sent from my Amstrad PC 1640 Never throw anything away, Griff Bad command or file name. Bad, bad command! Sit! Stay! Staaaay... AntiTwitter: @DalekDave is now a follower!
-
As I read [Adam Storr - Playing with C# 7 - Deconstruct](https://adamstorr.azurewebsites.net/blog/playing-with-csharp-7-deconstruct?utm\_source=Main&utm\_campaign=0cdc8b3a40-EMAIL\_CAMPAIGN\_2017\_12\_19\_COPY\_01&utm\_medium=email&utm\_term=0\_aa2f642d94-0cdc8b3a40-227561569&mc\_cid=0cdc8b3a40&mc\_eid=8087c9508d), I kept hoping that it would answer at long last the question of how to do
within C#. Alas, it fell short again. Does anybody besides me wish that C# supportedwithblocks, or have I overlooked a seriously underused language feature?David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
-
As I read [Adam Storr - Playing with C# 7 - Deconstruct](https://adamstorr.azurewebsites.net/blog/playing-with-csharp-7-deconstruct?utm\_source=Main&utm\_campaign=0cdc8b3a40-EMAIL\_CAMPAIGN\_2017\_12\_19\_COPY\_01&utm\_medium=email&utm\_term=0\_aa2f642d94-0cdc8b3a40-227561569&mc\_cid=0cdc8b3a40&mc\_eid=8087c9508d), I kept hoping that it would answer at long last the question of how to do
within C#. Alas, it fell short again. Does anybody besides me wish that C# supportedwithblocks, or have I overlooked a seriously underused language feature?David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
Many years ago, I wrote an expression evaluator for a Pascal compiler. "With" provided extra levels of complexity, which made me dislike it. "With" in VB leads to ambiguities when nested as you can have multiple sets of 'withed' variables in the same inner block. 'with' (now deprecated) in JavaScript lead to ambiguities where you could loop the 'with' and variables in the same construct could be global in one pass and local in subsequent passes. Used carefully, "With" can be a convenient shortcut; but it can be used badly. If you give people knives, they may whittle beautiful sculptures, but they are more likely to injure themselves or someone else.
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I don't miss Basic, either, but I miss that construct, which came to my attention when it became part of VBA as it manifested in Microsoft Access 2.0.
David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
Real men don't code in VB, or use any of its bastard constructs, such as
withorgoto.".45 ACP - because shooting twice is just silly" - JSOP, 2010
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You can never have too much ammo - unless you're swimming, or on fire. - JSOP, 2010
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When you pry the gun from my cold dead hands, be careful - the barrel will be very hot. - JSOP, 2013 -
BillWoodruff wrote:
I think it's a mistake to try and "bend" C# to fit your background in anothr language.
I'd agree - and suspect that's what a lot of the recent C# changes have been driven by: VB and C++ developers which want to continue writing VB and C++ code in C# instead of learning a newer, fresher language paradigm. And maybe that's why C# is getting "bloated" and losing it's focus as a coherent language.
Sent from my Amstrad PC 1640 Never throw anything away, Griff Bad command or file name. Bad, bad command! Sit! Stay! Staaaay... AntiTwitter: @DalekDave is now a follower!
OriginalGriff wrote:
VB and C++ developers which want to continue writing VB and C++ code in C# instead of learning a newer, fresher language paradigm
Not to mention it will rightly piss off the other members of your team when they run across your code in the project.
".45 ACP - because shooting twice is just silly" - JSOP, 2010
-----
You can never have too much ammo - unless you're swimming, or on fire. - JSOP, 2010
-----
When you pry the gun from my cold dead hands, be careful - the barrel will be very hot. - JSOP, 2013 -
Surely, you jest.
with Foo {
.Bar = 123;
.Baz = @"Zap!";
.Goo = 3.14159;
.Ergo = 1.1414141414l4;
}David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
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Many years ago, I wrote an expression evaluator for a Pascal compiler. "With" provided extra levels of complexity, which made me dislike it. "With" in VB leads to ambiguities when nested as you can have multiple sets of 'withed' variables in the same inner block. 'with' (now deprecated) in JavaScript lead to ambiguities where you could loop the 'with' and variables in the same construct could be global in one pass and local in subsequent passes. Used carefully, "With" can be a convenient shortcut; but it can be used badly. If you give people knives, they may whittle beautiful sculptures, but they are more likely to injure themselves or someone else.
I got the same speak a few years ago when I would introduce LINQ into an answer because I was not catering to the lowest common denominator. Those same people now have no issues with it. (LINQ)
"(I) am amazed to see myself here rather than there ... now rather than then". ― Blaise Pascal
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Foo.Bar = 123;
Foo.Baz = @"Zap!";
Foo.Goo = 3.14159;
Foo.Ergo = 1.1414141414l4;is two lines shorter :)
noop()
So? How many more characters, each requiring a keystroke, does your proposal require?
David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
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Many years ago, I wrote an expression evaluator for a Pascal compiler. "With" provided extra levels of complexity, which made me dislike it. "With" in VB leads to ambiguities when nested as you can have multiple sets of 'withed' variables in the same inner block. 'with' (now deprecated) in JavaScript lead to ambiguities where you could loop the 'with' and variables in the same construct could be global in one pass and local in subsequent passes. Used carefully, "With" can be a convenient shortcut; but it can be used badly. If you give people knives, they may whittle beautiful sculptures, but they are more likely to injure themselves or someone else.
Quote:
Used carefully, "With" can be a convenient shortcut; but it can be used badly. If you give people knives, they may whittle beautiful sculptures, but they are more likely to injure themselves or someone else.
The same can be said of almost every construct in any programming language. I'll take my chances. Using programming languages requires wisdom, a commodity that is, unfortunately, in very short supply.
David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
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Did I see the code sample that would never compile [^]: yes. Did I see a reference in another post you made to something "illustrated" without explanation: yes.
David A. Gray wrote:
Do you like typing the class name in front of every member name in a code block that sets ten properties one after another?
I do not see how this "sucker-punch question" is relevant to anything discussed here :) Beginning with the object initializer syntax in C# (C# 3.0, .NET 3.5), initializing a bunch of whatever when a new object was created became much easier. What's your issue here ? If you want to simulate 'With, techniques are well known, for a long time (see my post here). Now, if you have a better way, that doesn't use reflection, or the usual Extension Method: I'm all ears !
«Where is the Life we have lost in living? Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?» T. S. Elliot
It was a random thought, intended to generate the sort of discussion that has ensued. As a practical matter, I use object initializers, overloaded constructors, and constructors that have optional arguments almost exclusively. Unfortunately, this isn't always a workable option; thankfully, those times are rare.
David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
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It was a random thought, intended to generate the sort of discussion that has ensued. As a practical matter, I use object initializers, overloaded constructors, and constructors that have optional arguments almost exclusively. Unfortunately, this isn't always a workable option; thankfully, those times are rare.
David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
David A. Gray wrote:
It was a random thought, intended to generate the sort of discussion that has ensued.
One of the best excuses I've seen on this forum, but, an excuse for what ? But, I'm so happy you have random thoughts that you realize (later?) come from a place of deep wisdom and are, obviously, evidence of your sublime intelligence generously helping mere mortals to say what needs to be said :wtf:
«Where is the Life we have lost in living? Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?» T. S. Elliot
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It was a random thought, intended to generate the sort of discussion that has ensued. As a practical matter, I use object initializers, overloaded constructors, and constructors that have optional arguments almost exclusively. Unfortunately, this isn't always a workable option; thankfully, those times are rare.
David A. Gray Delivering Solutions for the Ages, One Problem at a Time Interpreting the Fundamental Principle of Tabular Reporting
Well, it did generate discussion :) And, I wouldn't mind having a 'With, or a special flavor of 'Using. cheers, Bill
«Where is the Life we have lost in living? Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?» T. S. Elliot
