Re: [boost] painless currying

On Aug 24, 2011, at 1:38 PM, Dave Abrahams wrote:

I mean this, for a ternary function f:

f(x) => doesn't call f f(x)(y) => doesn't call f f(x)(y)(z) => calls f

That last step looks asymmetric to me.

In a lazy language, f(x)(y)(z) *doesn't* call f... until you actually use the result for something... which is more consistent-looking.

I suppose the symmetrical non-lazy version looks like:

f(x) => doesn't call f f(x)(y) => doesn't call f f(x)(y)(z) => doesn't call f f(x)(y)(z)() => calls f

What about using [] for currying and () for calling? f[x] => returns binary function f[x][y] => returns unary function f[x][y][z] => returns nullary function All of these have the same effect: f(x, y, z) f[x](y, z) f[x][y](z) f[x][y][z]() Josh