digitalmars.D.learn - Conditionally set nothrow: for a block of code.
- Mike Franklin (62/62) May 24 2018 I'm trying to find a way to declare a block of code `nothrow:`
- Steven Schveighoffer (7/10) May 24 2018 My recommendation would have been the last one, but if that doesn't
- Uknown (10/22) May 27 2018 I think conditional application of attributes would be something
- Nicholas Wilson (3/7) May 28 2018 Not one now but, DIP 1012 will allow this as nothrow will become
- Mike Franklin (25/30) May 28 2018 Walter came up with a solution to this; put the code that is
I'm trying to find a way to declare a block of code `nothrow:` when compiling with -betterC, but not `nothrow` when not compiling with -betterC. The solution is needed for this PR: https://github.com/dlang/druntime/pull/2184/files#r188627707 ---------- void test() { } version(D_BetterC) { nothrow: } extern(C) void main() { test(); // This should throw an error in -betterC because `main` is // `nothrow` but `test` isn't. It doesn't work } ---------- version(D_BetterC) { enum isNoThrow = true; } else { enum isNoThrow = false; } void test() { } static if (isNoThrow) { nothrow: } extern(C) void main() { test(); // This should throw an error in -betterC because `main` is // `nothrow` but `test` isn't. It doesn't work } ---------- version(D_BetterC) { enum nothrowValue = "nothrow:"; } else { enum nothrowValue = ""; } void test() { } mixin(nothrowValue); extern(C) void main() { test(); // This should throw an error in -betterC because `main` is // `nothrow` but `test` isn't. It doesn't work } Given that the PR above is for object.d, I can't turn the entire object.d source file into a string and conditionally mix that in. Does anyone have a solution to this? Thanks, Mike
May 24 2018
On 5/24/18 2:51 PM, Mike Franklin wrote:Given that the PR above is for object.d, I can't turn the entire object.d source file into a string and conditionally mix that in. Does anyone have a solution to this?My recommendation would have been the last one, but if that doesn't work, I don't think anything will that is... palatable. The only other avenue you *could* explore is importing a file as a string and mixing the whole thing in (prepending "nothrow:" at the top). Other than that, I think it's on to DIP territory. -Steve
May 24 2018
On Thursday, 24 May 2018 at 18:51:31 UTC, Mike Franklin wrote:I'm trying to find a way to declare a block of code `nothrow:` when compiling with -betterC, but not `nothrow` when not compiling with -betterC. The solution is needed for this PR: https://github.com/dlang/druntime/pull/2184/files#r188627707 [...] Given that the PR above is for object.d, I can't turn the entire object.d source file into a string and conditionally mix that in. Does anyone have a solution to this? Thanks, MikeI think conditional application of attributes would be something useful. Something like this: version (D_BetterC) enum BetterC = true; else enum BetterC = false; nothrow!(BetterC): ... Of course that would require a DIP though
May 27 2018
On Thursday, 24 May 2018 at 18:51:31 UTC, Mike Franklin wrote:I'm trying to find a way to declare a block of code `nothrow:` when compiling with -betterC, but not `nothrow` when not compiling with -betterC. [...]Not one now but, DIP 1012 will allow this as nothrow will become a regular enum attribute.
May 28 2018
On Thursday, 24 May 2018 at 18:51:31 UTC, Mike Franklin wrote:I'm trying to find a way to declare a block of code `nothrow:` when compiling with -betterC, but not `nothrow` when not compiling with -betterC. The solution is needed for this PR: https://github.com/dlang/druntime/pull/2184/files#r188627707Walter came up with a solution to this; put the code that is conditionally `nothrow` in a template and mix it in in the appropriate branch. void test() { } mixin template code() { extern(C) void main() { test(); // This should throw an error in -betterC because `main` is // `nothrow` but `test` isn't. It doesn't work } } version(D_BetterC) { nothrow: mixin code; } else { mixin code; } Thanks, Walter. Mike
May 28 2018