On 17/03/2013, at 12:16, Jason Orendorff wrote: > On Sun, Mar 17, 2013 at 2:43 AM, Claus Reinke <[email protected]> wrote: > Neither arguments.callee (not available in strict) nor let (clumsy to > use in expressions) are needed for self-reference > > var rec = (f) => f((...args)=>rec(f)(...args)); > > var f = (self)=>(n)=> n>1 ? n*self(n-1) : n; > > [1,2,3,4,5,6].map((n)=>rec(f)(n)); > > ...but then you have a function rec which self-references. Much better to use > the Z combinator: > > f => (x => f(v => x(x)(v)))(x => f(v => x(x)(v))) > > which can be conveniently inlined into any expression where it's used: > > js> [1,2,3,4,5,6].map((n)=>(f => (x => f(v => x(x)(v)))(x => f(v => > x(x)(v))))(self => n => n>1 ? n*self(n-1) : n)(n)); > [1, 2, 6, 24, 120, 720] > > Obviously this is much better than arguments.callee.
:-) And I want to tear out my eyes! -- (Jorge)(); _______________________________________________ es-discuss mailing list [email protected] https://mail.mozilla.org/listinfo/es-discuss
