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copied!<p>You are missing dimensional analysis. For example (from the answer you linked to), in F# you can do this:</p> <pre><code>let g = 9.8<m/s^2> </code></pre> <p>and it will generate a new unit of acceleration, derived from meters and seconds (you can actually do the same thing in C++ using templates).</p> <p>In C#, it is possible to do dimensional analysis at runtime, but it adds overhead and doesn't give you the benefit of compile-time checking. As far as I know there's no way to do full compile-time units in C#.</p> <p>Whether it's worth doing depends on the application of course, but for many scientific applications, it's definitely a good idea. I don't know of any existing libraries for .NET, but they probably exist.</p> <p>If you are interested in how to do it at runtime, the idea is that each value has a scalar value and integers representing the power of each basic unit.</p> <pre><code>class Unit { double scalar; int kg; int m; int s; // ... for each basic unit public Unit(double scalar, int kg, int m, int s) { this.scalar = scalar; this.kg = kg; this.m = m; this.s = s; ... } // For addition/subtraction, exponents must match public static Unit operator +(Unit first, Unit second) { if (UnitsAreCompatible(first, second)) { return new Unit( first.scalar + second.scalar, first.kg, first.m, first.s, ... ); } else { throw new Exception("Units must match for addition"); } } // For multiplication/division, add/subtract the exponents public static Unit operator *(Unit first, Unit second) { return new Unit( first.scalar * second.scalar, first.kg + second.kg, first.m + second.m, first.s + second.s, ... ); } public static bool UnitsAreCompatible(Unit first, Unit second) { return first.kg == second.kg && first.m == second.m && first.s == second.s ...; } } </code></pre> <p>If you don't allow the user to change the value of the units (a good idea anyways), you could add subclasses for common units:</p> <pre><code>class Speed : Unit { public Speed(double x) : base(x, 0, 1, -1, ...); // m/s => m^1 * s^-1 { } } class Acceleration : Unit { public Acceleration(double x) : base(x, 0, 1, -2, ...); // m/s^2 => m^1 * s^-2 { } } </code></pre> <p>You could also define more specific operators on the derived types to avoid checking for compatible units on common types.</p>

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