digitalmars.D - Warnings about potential loss of data
- Derek Parnell <derek psych.ward> Feb 06 2006
- Sean Kelly <sean f4.ca> Feb 06 2006
- "Matthew" <matthew hat.stlsoft.dot.org> Feb 06 2006
- Stewart Gordon <smjg_1998 yahoo.com> Feb 07 2006
- U.Baumanis <U.Baumanis_member pathlink.com> Feb 07 2006
- "Derek Parnell" <derek psych.ward> Feb 07 2006
- Don Clugston <dac nospam.com.au> Feb 07 2006
Assuming that the idea behind the "-w" switch is to help coders locate the
assumptions that the compiler is making on our behalf, I think that it
would be useful to add an "optional error" when the compiler detects a
potential loss of data.
Example 1:
import std.stdio;
void main()
{
uint a;
int b;
b = -3;
a = b; // A warning here would be appreciated.
writefln("a = ", a, ", b = ", b);
// result: a = 4294967293, b = -3
}
Example 2:
void Foo()
{
int a;
long b;
b = SomeFunction();
a = b; // A warning here would be appreciated.
}
and there are many other examples too.
--
Derek
(skype: derek.j.parnell)
Melbourne, Australia
"Down with mediocracy!"
7/02/2006 11:16:27 AM
Feb 06 2006
Derek Parnell wrote:Assuming that the idea behind the "-w" switch is to help coders locate the assumptions that the compiler is making on our behalf, I think that it would be useful to add an "optional error" when the compiler detects a potential loss of data.
Agreed. I'd like the compiler to warn me about narrowing conversions that don't use an explicit cast. Sean
Feb 06 2006
"Matthew" <matthew hat.stlsoft.dot.org> "Sean Kelly" <sean f4.ca> wrote in message news:ds8pmm$ups$1 digitaldaemon.com...Derek Parnell wrote:Assuming that the idea behind the "-w" switch is to help coders locate
assumptions that the compiler is making on our behalf, I think that it would be useful to add an "optional error" when the compiler detects a potential loss of data.
Agreed. I'd like the compiler to warn me about narrowing conversions that don't use an explicit cast.
Wistfully ROFL!
Feb 06 2006
Derek Parnell wrote:Assuming that the idea behind the "-w" switch is to help coders locate the assumptions that the compiler is making on our behalf, I think that it would be useful to add an "optional error" when the compiler detects a potential loss of data.
What is an "optional error"? Either a piece of code is legal, or it isn't, surely? <snip>Example 2: void Foo() { int a; long b; b = SomeFunction(); a = b; // A warning here would be appreciated. }
I'd like this to be an error. Stewart. -- -----BEGIN GEEK CODE BLOCK----- Version: 3.1 GCS/M d- s:- C++ a->--- UB P+ L E W++ N+++ o K- w++ O? M V? PS- PE- Y? PGP- t- 5? X? R b DI? D G e++>++++ h-- r-- !y ------END GEEK CODE BLOCK------ My e-mail is valid but not my primary mailbox. Please keep replies on the 'group where everyone may benefit.
Feb 07 2006
In article <dsa2nv$1v8q$1 digitaldaemon.com>, Stewart Gordon says...What is an "optional error"? Either a piece of code is legal, or it isn't, surely? <snip>Example 2: void Foo() { int a; long b; b = SomeFunction(); a = b; // A warning here would be appreciated. }
I'd like this to be an error. Stewart.
-- UB
Feb 07 2006
On Tue, 07 Feb 2006 23:10:39 +1100, Stewart Gordon <smjg_1998 yahoo.com> wrote:Derek Parnell wrote:Assuming that the idea behind the "-w" switch is to help coders locate the assumptions that the compiler is making on our behalf, I think that it would be useful to add an "optional error" when the compiler detects a potential loss of data.
What is an "optional error"? Either a piece of code is legal, or it isn't, surely?
It was from something that Walter said about "-w" warnings ... 'Think of them as "optional errors" instead of warnings <g>.' - Walter -- Derek Parnell Melbourne, Australia
Feb 07 2006
Derek Parnell wrote:On Tue, 07 Feb 2006 23:10:39 +1100, Stewart Gordon <smjg_1998 yahoo.com> wrote:Derek Parnell wrote:Assuming that the idea behind the "-w" switch is to help coders locate the assumptions that the compiler is making on our behalf, I think that it would be useful to add an "optional error" when the compiler detects a potential loss of data.
What is an "optional error"? Either a piece of code is legal, or it isn't, surely?
It was from something that Walter said about "-w" warnings ... 'Think of them as "optional errors" instead of warnings <g>.' - Walter
"pedantic errors" might be a better term. I think that what you're doing is telling the compiler something about your coding style (and perhaps, what kinds of bugs you create).
Feb 07 2006