digitalmars.D.bugs - [Issue 3715] New: std.string.format can't use const/immutable toString functions
- d-bugmail puremagic.com (31/31) Jan 17 2010 http://d.puremagic.com/issues/show_bug.cgi?id=3715
- d-bugmail puremagic.com (12/12) Sep 17 2010 http://d.puremagic.com/issues/show_bug.cgi?id=3715
- d-bugmail puremagic.com (14/14) Sep 18 2010 http://d.puremagic.com/issues/show_bug.cgi?id=3715
- d-bugmail puremagic.com (8/11) Sep 19 2010 http://d.puremagic.com/issues/show_bug.cgi?id=3715
- d-bugmail puremagic.com (20/20) Sep 20 2010 http://d.puremagic.com/issues/show_bug.cgi?id=3715
- d-bugmail puremagic.com (6/8) Dec 02 2010 Looks like this is "fixed", see bug 3797.
- d-bugmail puremagic.com (12/12) Dec 21 2012 http://d.puremagic.com/issues/show_bug.cgi?id=3715
http://d.puremagic.com/issues/show_bug.cgi?id=3715 Summary: std.string.format can't use const/immutable toString functions Product: D Version: 2.036 Platform: All OS/Version: All Status: NEW Severity: normal Priority: P2 Component: Phobos AssignedTo: nobody puremagic.com ReportedBy: tomeksowi gmail.com PST --- Test case: struct A { string toString() const { return "A"; } } void main() { writeln(format("%s", A())); } Outputs: std.format.FormatError: std.format Can't convert test.A to string: "string toStr ing()" not defined Same for immutable. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Jan 17 2010
http://d.puremagic.com/issues/show_bug.cgi?id=3715 Jonathan M Davis <jmdavisProg gmx.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |jmdavisProg gmx.com PDT --- nothrow and pure don't work either. My guess is that toString() must have the _exact_ signature of public string toString() or it doesn't work with format(), so _no_ other function modifiers can be used on it. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Sep 17 2010
http://d.puremagic.com/issues/show_bug.cgi?id=3715 Steven Schveighoffer <schveiguy yahoo.com> changed: What |Removed |Added ---------------------------------------------------------------------------- CC| |schveiguy yahoo.com 10:33:52 PDT --- Yes, std.string.format uses varargs, not templates, so it can only do what the TypeInfo allows it to do. And the compiler will only store the function pointer to toString if it exactly matches the right signature. See some related discussion in http://d.puremagic.com/issues/show_bug.cgi?id=4290 -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Sep 18 2010
http://d.puremagic.com/issues/show_bug.cgi?id=3715 PDT ---Yes, std.string.format uses varargs, not templates, so it can only do what the TypeInfo allows it to do. And the compiler will only store the function pointer to toString if it exactly matches the right signature.OK, now I understand why it doesn't work, thanks. But how to get it working? In real life toString() will often be const|pure|nothrow because of its nature. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Sep 19 2010
http://d.puremagic.com/issues/show_bug.cgi?id=3715 04:36:35 PDT --- Well, first of all, toString should always be const. But pure and nothrow are two options that are also valid. I think some real thought needs to go into delegates and function pointers, and what can implicitly cast. Right now, there are no implicit casts between function pointers (except const casts which are invalid anyways). As a workaround, you can do something like this: struct A { /*pure nothrow?*/ string toString() const { return "A"; } string toString() {const(A)*me = &this; return me.toString();} } What this does is put a common implementation for each overload so you don't have to rewrite it. When the requirements change (and they will, because toString should be const), then in most cases you can just get away with a const function. If you want to have pure and nothrow available, then you still have to do something like this. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Sep 20 2010
http://d.puremagic.com/issues/show_bug.cgi?id=3715 22:11:40 PST ---Right now, there are no implicit casts between function pointers (except const casts which are invalid anyways).Looks like this is "fixed", see bug 3797. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Dec 02 2010
http://d.puremagic.com/issues/show_bug.cgi?id=3715 Andrej Mitrovic <andrej.mitrovich gmail.com> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEW |RESOLVED CC| |andrej.mitrovich gmail.com Resolution| |FIXED 09:09:38 PST --- Fixed in 2.060. -- Configure issuemail: http://d.puremagic.com/issues/userprefs.cgi?tab=email ------- You are receiving this mail because: -------
Dec 21 2012