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_xaperture.js
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/
_xaperture.js
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import _concat from './_concat.js';
import _curry2 from './_curry2.js';
import _xfBase from './_xfBase.js';
function XAperture(n, xf) {
this.xf = xf;
this.pos = 0;
this.full = false;
this.acc = new Array(n);
}
XAperture.prototype['@@transducer/init'] = _xfBase.init;
XAperture.prototype['@@transducer/result'] = function(result) {
this.acc = null;
return this.xf['@@transducer/result'](result);
};
XAperture.prototype['@@transducer/step'] = function(result, input) {
this.store(input);
return this.full ? this.xf['@@transducer/step'](result, this.getCopy()) : result;
};
XAperture.prototype.store = function(input) {
this.acc[this.pos] = input;
this.pos += 1;
if (this.pos === this.acc.length) {
this.pos = 0;
this.full = true;
}
};
XAperture.prototype.getCopy = function() {
return _concat(Array.prototype.slice.call(this.acc, this.pos),
Array.prototype.slice.call(this.acc, 0, this.pos)
);
};
var _xaperture = _curry2(function _xaperture(n, xf) { return new XAperture(n, xf); });
export default _xaperture;