Bug 7476 – Write(ln) functions no longer accept retro range

import std.stdio, std.range; void main() { write(retro("abcd")); } Dmd outputs: std\range.d(295): Error: static assert "Cannot put a Result into a LockingTextWriter" std\format.d(1509): instantiated from here: put!(LockingTextWriter,Result) std\format.d(1984): instantiated from here: formatRange!(LockingTextWriter,Result,char) std\format.d(2228): instantiated from here: formatValue!(LockingTextWriter,Result,char) std\format.d(319): instantiated from here: formatGeneric!(LockingTextWriter,Result,char) std\stdio.d(684): instantiated from here: formattedWrite!(LockingTextWriter,char,Result) std\stdio.d(1503): instantiated from here: write!(Result) retro.d(5): instantiated from here: write!(Result) This worked on 2.057.

Works for me. Windows 7 64bit - Service Pack 1 C:\Users\Kevin\Documents\D Projects\ConsoleApp1\ConsoleApp1\bin>where dmd C:\D\dmd\windows\bin\dmd.exe C:\D\dmd2\windows\bin\dmd.exe C:\Users\Kevin\Documents\D Projects\ConsoleApp1\ConsoleApp1\bin>C:\D\dmd2\windows\bin\dmd.exe ..\main.d C:\Users\Kevin\Documents\D Projects\ConsoleApp1\ConsoleApp1\bin>main.exe dcba C:\Users\Kevin\Documents\D Projects\ConsoleApp1\ConsoleApp1\bin>type ..\main.d import std.stdio, std.range; void main() { write(retro("abcd")); } C:\Users\Kevin\Documents\D Projects\ConsoleApp1\ConsoleApp1\bin>C:\D\dmd2\windows\bin\dmd.exe DMD32 D Compiler v2.057 Copyright (c) 1999-2011 by Digital Mars written by Walter Bright Documentation: http://www.digitalmars.com/d/2.0/index.html Usage: --- truncate ---

Wait, I'm confused. You said it works on 2.057 (which I can confirm). What version is it not working on? 2.057 is the latest.

> Wait, I'm confused. You said it works on 2.057 (which I can confirm). What > version is it not working on? 2.057 is the latest. The latest on github (and the current 2.058 beta).

Just downloaded the git source and compiled with dmc Works for me on latest version. 2.048 Beta c:\Users\Kevin\Documents\D Projects\ConsoleApp1\ConsoleApp1\bin>dmd ../main.d DMD v2.058 DEBUG c:\Users\Kevin\Documents\D Projects\ConsoleApp1\ConsoleApp1\bin>main.exe dcba c:\Users\Kevin\Documents\D Projects\ConsoleApp1\ConsoleApp1\bin>

I've got to stop typing at 2 in the morning... I mean 2.058 Debug, as shown in the console dump. (In reply to comment #4) > Just downloaded the git source and compiled with dmc > > Works for me on latest version. 2.048 Beta

I think it is a regression in Phobos. Have you compiled against Phobos 2.057 or Phobos 2.058head?

A shallow answer: 2.058 was merged a pull to improve std.format: https://github.com/D-Programming-Language/phobos/pull/298 and after that this regression has been occurred. A deep answer: This is a problem rooted in the std.range.put implementation. reduced code: ---- import std.range; struct LockingTextWriter { void put(dchar c){} } struct RetroResult { bool end = false; @property bool empty() const { return end; } @property dchar front(){ return 'a'; } void popFront(){ end = true; } } void main() { LockingTextWriter w; RetroResult r; put(w, r); // test.d(20) } Output: ---- C:\dmd2\src\phobos\std\range.d(295): Error: static assert "Cannot put a RetroResult into a LockingTextWriter" test.d(20): instantiated from here: put!(LockingTextWriter,RetroResult) Current std.format.formatValue treats retro("abcd") as a kind of string range. And try to put it into Writer by using std.range.put(). void put(R, E)(ref R r, E e) // std.range.put signature When E is an array (of cause it is random access range), put() runs the range-to-range copy. But put() cannot instantiate with E that isn't array range.

*** Issue 7531 has been marked as a duplicate of this issue. ***

Commit pushed to master at https://github.com/D-Programming-Language/phobos https://github.com/D-Programming-Language/phobos/commit/3a03376c7d6b8b5b998aa5c3e0dfd9837e3198dc Merge pull request #426 from 9rnsr/fix7476 Issue 7476 - Write(ln) functions no longer accept retro range

*** Issue 7433 has been marked as a duplicate of this issue. ***