Coding/Naming Conventions

[Brian Padalino]

I recently downloaded the OSVVM package and was looking it over.  Something that was striking was the naming conventions in the packages which seemed, to me, somewhat inconsistent.

For an example, I am looking at RandomPkg.vhd in the package declaration.  One observation is that VHDL is insensitive to case, so DISTTYPE is the same as DistType.  Personally, I prefer _p for packages, _t for types, but that is just a style preference.

My main comment comes in the Rand<Type>; functions.  It seems that subprogram overloading is done above (favor_small, favor_big, normal, uniform, etc) but then there are a slew of RandReal, RandInt, RandSLV, RandUnsigned, RandSigned.  Should these functions be overloaded to just Rand with the different signatures?

A small gripe is with the naming of functions that are comprised of different words.  Some are camelCase (InitSeed, SetRandomMode) while others have underscores (Favor_big, Favor_small).  As alluded to beforehand, I prefer underscores since VHDL doesn’t care about case and the standard libraries tend to prefer underscores, but sticking to a single convention would be nice.

[Jim Lewis]

I agree with the issue WRT favor_big and favor_small. It was an oversight from the translation from RandomDistType.  I made a note to change them to FavorBig and FavorSmall in the next revision.  Everything else that uses “_” is either a constant (and is upper case) or an externally defined type or subprogram.   

I avoided an overloaded Rand due to ambiguity of expressions, such as the following:

wait for RV.Rand(1,6) * TPeriod_Clk ;

Make sure to also look at CoveragePkg as I do my first line of randomization using RandCovPoint

As an aside about RandomDistType/SetRandomMode/SetRandomParm, I suspect they will go away in a future version. Since all of the functions that they allowed calling can now able to be called directly, I am not sure the overhead of supporting this is justified.

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