Refactored mandatory ptr parameter to reference.

[lewie-donckers]

Refactored a mandatory (nullptr is not allowed) pointer parameter to a reference.

See:

• https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#f17-for-in-out-parameters-pass-by-reference-to-non-const
• https://isocpp.github.io/CppCoreGuidelines/CppCoreGuidelines#f60-prefer-t-over-t-when-no-argument-is-a-valid-option

[Rayman]

Google style guide (and cpplint) used to recommend output parameters to be pointer so that you can see an argument is modified:

foo(x, y);     // x and y won't be mutated
bar(x, &y);    // y may be mutated

But I can't find it in the style guide anymore, is this rule outdated? https://google.github.io/styleguide/cppguide.html#Inputs_and_Outputs

[lewie-donckers]

But I can't find it in the style guide anymore, is this rule outdated?

I hope so. ;-D