CPP11 1.1 RTF Avatar
  1. OMG Issue

CPP1111 — Fixed type mapping should provide (explicit) operator bool

  • Key: CPP1111-10
  • Legacy Issue Number: 18405
  • Status: closed  
  • Source: gmail.com ( daniel.kruegler@gmail.com)
  • Summary:

    Given the specification of the class template Fixed provides

    operator int64_t () const;
    operator long double() const;


    bool operator!() const;

    This allows to test some Fixed instantiation within a boolean context as in a useful way as follows:

    typedef IDL::Fixed<5,2> F;
    F f = ...;
    if (!f)

    { ... }

    But the similar inverse form

    if (f) { ... }

    will cause an ambiguity error between the two conversion functions to int64_t and long double. User code is required to write the obfuscated form

    if (!!f)

    { ... }

    to realize the same thing. This is unfortunate and there is a simple means to solve this problem: The specification should add

    explicit operator bool() const;

    to the class template synopsis with the same semantics as negating operator!

  • Reported: CPP11 1.0b2 — Fri, 1 Feb 2013 05:00 GMT
  • Disposition: Resolved — CPP11 1.1
  • Disposition Summary:

    Accepting this issue as proposed. Also during the discussion it was proposed to add a
    namespace level to_string

  • Updated: Fri, 6 Mar 2015 20:58 GMT