cat > bug.d << CODE
import std.array, std.format, std.range;

void foo()
{
    Appender!string app;
    // this is broken
    app.put("foo");
    // => broken std.range.put
    std.range.put(app, "foo");
    // => broken std.format.formattedWrite
    formattedWrite(app, "%s", "foo");
    // => ...
}
CODE

dmd -c bug

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