c4606b84329d760d7cee144bebe05807857edaae Add Travis check for single parameter constructors not marked "explicit" (practicalswift)
Pull request description:
Make single parameter constructors `explicit` (C++11).
Rationale from the developer notes:
> - By default, declare single-argument constructors `explicit`.
> - *Rationale*: This is a precaution to avoid unintended conversions that might
> arise when single-argument constructors are used as implicit conversion
> functions.
ACKs for top commit:
laanwj:
ACK c4606b84329d760d7cee144bebe05807857edaae
Tree-SHA512: 3e6fd51935fd93b2604b2188664692973d0897469f814cd745b5147d71b99ea5d73c1081cfde9f6393f51f56969e412fcda35d2d54e938a3235b8d40945f31fd
