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Probably because it was modelled on languages which do allow execution to fall-through, and without an explicit break / return, early adopters might have thought the C# code was falling through.
[Proposal] Case fall through should be allowed · dotnet/csharplang · Discussion #603 · GitHub[^]
See also Eric Lippert's comments on SO:
C# enforces the no-fall-through rule in every switch section, including the last one. This is so that switch sections can be re-ordered arbitrarily, possibly by mechanical tools, without introducing semantic changes in the program.
C# enforces the no-fall-through rule by requiring that the end point of every switch section be unreachable. It is not necessary for a switch section to end in a break. It can end in a break, return, goto, continue, throw, or a detectable infinite loop:
"These people looked deep within my soul and assigned me a number based on the order in which I joined."
- Homer
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For the most common scenario it just adds a line of code that has to be written which has no meaning.
It just clutters the code with additional meaningless lines. Bah, or better, ![Sheep | [baah]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/sheep.gif) !
GCS/GE d--(d) s-/+ a C+++ U+++ P-- L+@ E-- W+++ N+ o+ K- w+++ O? M-- V? PS+ PE Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
The shortest horror story: On Error Resume Next
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Richard Deeming wrote: detectable infinite loop
Classic! You won't find any of my switch statements without one of those. 
Regards,
Rob Philpott.
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I agree with a specific "end of case" being required - as Richard quoted, it allows the compiler to spot code faults instead of letting them cause runtime problems.
It may be "unnecessary", but it does trap some errors which could be difficult to diagnose at run time.
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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It does allow multiple "entry points", so
case 1:
case 2:
Some code
break;
So it can't just assume a break. Sure they can come up with rules for how it would be interpreted, but kind of glad they didn't.
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Personally, I'd have preferred multiple entries to be a different syntax:
case 1,
2,
3:
... code
break;
case 4:
... code
break;Or even:
case 1,
2,
3:
{
... code
break;
}
case 4:
{
... code
break;
}I think it would have been clearer as well as less easy to mess up by adding a new case between them. Perhaps with brackets round the case list as well?
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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OriginalGriff wrote: Or even:
case 1,
2,
3:
case 4:
The Pascal style (except for the 'break' statements). I don't like the C# 'No fallthrough except when the case alternative is empty', so I sort of agree with you, although it is not a big matter.
I do upset some people by always using braces, like in your second alternative: Indentation and braces go hand-in-hand. Call it 'two-factor level nesting'. I want to indent the case alternative, so it should be made a block. Blocks are indented. Statements are not, neither single nor multiple statements. In- and un-denting without braces makes a mess of nesting levels.
Religious freedom is the freedom to say that two plus two make five.
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I didn't know this (C# is not my main language) and now it makes sense. From the compiler errors I supposed it didn't allow multiple entry points as well, just like VB6 used to do.
GCS/GE d--(d) s-/+ a C+++ U+++ P-- L+@ E-- W+++ N+ o+ K- w+++ O? M-- V? PS+ PE Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
The shortest horror story: On Error Resume Next
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I blame Ken Thompson.
switch should never have had fall-through, break should never have affected switch. That should have been their first clue.
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I blame Ken Thompson for the vast majority of bugs in today's software. The entire concept of null terminated strings and buffers is simply asking for trouble. DEC and IBM both had descriptor-based buffers, which gives the OS calls that manipulate buffers a way to block buffer overflows.
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Nice, but... which OS?
There are no OS where we are going.
GCS/GE d--(d) s-/+ a C+++ U+++ P-- L+@ E-- W+++ N+ o+ K- w+++ O? M-- V? PS+ PE Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
The shortest horror story: On Error Resume Next
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Default fallthrough is one of the major reasons why C is called a machine independent assembler.
Or of you like: A yafi-ygi language.
Religious freedom is the freedom to say that two plus two make five.
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trønderen wrote: C is called a machine independent assembler.
That's why I love it
GCS/GE d--(d) s-/+ a C+++ U+++ P-- L+@ E-- W+++ N+ o+ K- w+++ O? M-- V? PS+ PE Y+ PGP t+ 5? X R+++ tv-- b+(+++) DI+++ D++ G e++ h--- r+++ y+++* Weapons extension: ma- k++ F+2 X
The shortest horror story: On Error Resume Next
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I will propose a related extension to C#: Default fall through to the next method.
If the flow runs out of a method body's closing brace, with no explicit return statement, execution continues to the following method.
This would be very useful e.g. for methods that take arguments of two different kinds, say integer and string: The first method would accept, say, a numeric string and convert it to a binary integer, then flowing on to the following method doing the processing on binary integers, regardless of which entry point was used. Fortran has (or had?) its ENTRY statement providing this kind of functionality.
While multiple entry points can be simulated by the first method explicitly calling the other, after format conversion, this adds a completely unnecessary statement, as well as a handful unnecessary instruction for the call management, and increased stack demands.
I cannot think of any single use case were switch case fall through is well justified, and where the arguments for it can not reasonably be extended to justify method fall through. If one makes sense, so does the other.
Religious freedom is the freedom to say that two plus two make five.
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yes, but the "new" switch expression 🤤
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Got an email from Dell that some of my data had been compromised. They don't think any financial data was stolen. Another one, sigh.
It seems to me that the people on the dark side have it much easier. I have to screw around with passwords, text messages, and some ugly Microsoft security application on my phone to get to my data.
They just click. Doesn't seem right.
Oh well, every hundred years, all new people.
>64
It’s weird being the same age as old people. Live every day like it is your last; one day, it will be.
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The fact that the only thing you get from the companies is an email with vague excuses like "We f***ed up, and your data are compromised. We are sorry, but it will not happen gain. Well maybe, but honestly, we do not really care, as it has no influence on our business. Too bad you susbcribed !" when they are hacked is the worst part of all. They do poorly, your data is exposed, but the get away with a simple email. This is crazy.
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I'm rather selective about what information it is I'm being asked for, and if I can get away with BS answers, that's what they'll get.
I'd rather feed the beast that is Amazon and let them have my details, rather than spread around my credit card data to a dozen mom and pop shops who invest basically nothing to secure the data they collect.
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At this point in time I don't even pay attention to these notices. As far as I can tell my entire financial history is on the dark web.
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Sadly true. About 5 years ago (maybe more), I got a notice from the IRS (USofA) that my SSN was compromised and some kind soul had filed a tax return for me. They wanted the several million dollars I had submitted for estimated taxes. Seems as though some medical system employee had sold a large list of SSN's. I fretted about it for a few milliseconds, cracked open a Lou's Brew and took a nap.
(Actually, I don't/didn't submit estimated taxes just for this reason). I don't know what the right ponders equivalent of this is, but I am sure I am not alone.
I do have throw away email addresses and phone numbers I use.
>64
It’s weird being the same age as old people. Live every day like it is your last; one day, it will be.
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I had a charge Friday against my business Amex that is very rarely used, however I did buy a laptop from Dell with it. Someone bought $1200 worth of thermostats from Lowes using my Amex number, my name and phone number, and apparently the 4 digit Amex security code from the card. I am blaming Dell, as I think they even stored the 4 digit security code and it was exposed in the hack. Got it all cancelled, and new Amex card on the way, cost me an hour of my precious time to deal with it.
I have had my personal data exposed before, usually from govt databases, and their solution is to offer you 3 free years of Experian or some such. First step, give Experian all the sensitive that was just stolen. Ugh.
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wapiti64 wrote: free years of Experian
Yup, they did that as well. Good deal for Experian or whoever, they figure you will renew. We have all reporting turned off.
>64
It’s weird being the same age as old people. Live every day like it is your last; one day, it will be.
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theoldfool wrote: It seems to me that the people on the dark side have it much easier.
They also have cookies. 
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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