Created
January 1, 2012 00:59
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compose using bindify
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var b = require('bindify') | |
// first make a function that does \ a b -> \ c -> b(a c) | |
var compose_2 = b(b, null | |
, Function.prototype.call | |
, b._1 | |
, b._wrap(b._this) | |
, nested_b(nested_b, null | |
, b._0 | |
, b._wrap(b._this) | |
, b._wrap(b._argslice()))) | |
// now make a function that does \ a b c ... -> \ z -> ... c (b (a z)) | |
var compose = b(b, null | |
, compose_2( | |
b([].reduce, b._0 | |
, nested_b(compose_2, null | |
, nested_b(b, null | |
, Function.prototype.apply | |
, b._wrap(b._1) | |
, b._this | |
, b._wrap(b._0)) | |
, b([].slice, b._args)) | |
, b._1) | |
, b([].shift, b._0)) | |
, b._wrap(b._this), b._args, b._wrap(b._args)) | |
function nested_b() { | |
var func = b.apply(b, arguments) | |
function NestedB(args, thisobj, arr, arridx) { | |
if (arridx != -1) | |
arr[arridx++] = func.apply(thisobj, args) | |
return 1 } | |
b.specialify(NestedB) | |
return NestedB } | |
// compose beta-equivalent to: | |
function small_compose() { | |
var a = arguments | |
return function() { | |
var t = this | |
return [].reduce.call(a, function(p, c) { | |
return [c.apply(t, p)] }, arguments)[0] }} |
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