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Subject: Re: [v3 PATCH] Make the default constructors of tuple and pair conditionally explicit.
To: Ville Voutilainen <ville.voutilainen@gmail.com>
References: <CAFk2RUaUjmpsbvQdonwR2SaqjAMHk2tjaBrKjM1Gy8jmJg1Ufg@mail.gmail.com> <56377F0B.7070209@oracle.com> <CAFk2RUbWcCeQWdqeoR2x+W2nSgMR9fsGKZQAtFw6eXz8U6+MJA@mail.gmail.com>
Cc: "gcc-patches@gcc.gnu.org" <gcc-patches@gcc.gnu.org>, libstdc++@gcc.gnu.org
From: Paolo Carlini <paolo.carlini@oracle.com>
Message-ID: <5637B784.6020403@oracle.com>
Date: Mon, 02 Nov 2015 19:20:00 -0000
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Hi,

+  template <typename _Tp>
+    struct __is_implicitly_default_constructible
+      : public integral_constant<bool,
+                    (__and_<is_default_constructible<_Tp>,
+                            __is_implicitly_default_constructible_safe<_Tp>
+                           >::value)>


Can we follow the terse style already used elsewhere (eg, 
__is_direct_constructible_new_safe) thus directly inherit from __and_ 
and avoid explicit integral_constant? Otherwise patch looks good to me.

Thanks,
Paolo.