143 lines
No EOL
4.6 KiB
JavaScript
143 lines
No EOL
4.6 KiB
JavaScript
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var Elm = Elm || {};
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Elm.Signal = function() {
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var send = function(node, timestep, changed) {
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var kids = node.kids;
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for (var i = kids.length; i--; ) {
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kids[i].recv(timestep, changed, node.id);
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}
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};
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var input = function(base) {
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this.id = Guid.guid();
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this.value = base;
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this.kids = [];
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this.defaultNumberOfKids = 0;
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this.recv = function(timestep, eid, v) {
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var changed = eid === this.id;
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if (changed) { this.value = v; }
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send(this, timestep, changed);
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return changed;
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};
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Dispatcher.inputs.push(this);
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};
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var lift = function(func,args) {
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this.id = Guid.guid();
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this.value = null;
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this.kids = [];
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this.count = 0;
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this.changed = false;
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args.reverse();
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this.recalc = function() {
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var f = func;
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for (var i = args.length; i--; ) {
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f = f(args[i].value);
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}
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this.value = f;
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};
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this.recalc();
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this.recv = function(timestep, changed, parentID) {
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this.count += 1;
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if (changed) { this.changed = true; }
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if (this.count == args.length) {
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if (this.changed) { this.recalc() }
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send(this, timestep, this.changed);
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this.changed = false;
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this.count = 0;
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}
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};
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for (var i = args.length; i--; ) {
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args[i].kids.push(this);
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}
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};
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var fold = function(func,base,baseIsFunc,input) {
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this.id = Guid.guid();
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this.value = baseIsFunc ? base(input.value) : base;
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this.kids = [];
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this.recv = function(timestep, changed, parentID) {
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if (changed) { this.value = func(input.value)(this.value); }
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send(this, timestep, changed);
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};
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input.kids.push(this);
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};
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var dropIf = function(pred,base,input) {
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this.id = Guid.guid();
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this.value = pred(input.value) ? base : input.value;
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this.kids = [];
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this.recv = function(timestep, changed, parentID) {
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var chng = changed && !pred(input.value);
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if (chng) { this.value = input.value; }
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send(this, timestep, chng);
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};
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input.kids.push(this);
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};
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var dropRepeats = function(input) {
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this.id = Guid.guid();
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this.value = input.value;
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this.kids = [];
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this.recv = function(timestep, changed, parentID) {
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var chng = changed && !eq(this.value,input.value);
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if (chng) { this.value = input.value; }
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send(this, timestep, chng);
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};
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input.kids.push(this);
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};
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var dropWhen = function(s1) { return function(b) { return function(s2) {
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var pairs = new lift(function(x){return function(y){return [x,y];};},[s1,s2]);
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var dropped = new dropIf(function(p){return p[0];},[true,b],pairs);
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return new lift(function(p){return p[1];},[dropped]); }; };
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};
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var sampleOn = function(s1,s2) {
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this.id = Guid.guid();
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this.value = s2.value;
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this.kids = [];
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this.count = 0;
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this.changed = false;
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this.recv = function(timestep, changed, parentID) {
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if (parentID === s1.id) this.changed = changed;
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this.count += 1;
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if (this.count == 2) {
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if (this.changed) { this.value = s2.value; }
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send(this, timestep, this.changed);
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this.count = 0;
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this.changed = false;
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}
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};
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s1.kids.push(this);
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s2.kids.push(this);
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};
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return {
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constant : function(v) { return new input(v); },
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lift : function(f){return function(e){return new lift(f,[e]);};},
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lift2 : function(f) { return function(e1) { return function(e2) {
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return new lift(f, [e1,e2]); }; }; },
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lift3 : function(f) { return function(e1) { return function(e2) {
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return function(e3){return new lift(f,[e1,e2,e3]);};};};},
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lift4 : function(f) { return function(e1) { return function(e2) {
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return function(e3) { return function(e4) {
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return new lift(f, [e1,e2,e3,e4]); }; }; }; }; },
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foldp : function(f) { return function(b) { return function(e) {
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return new fold(f,b,false,e); }; }; },
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foldp_ : function(f) { return function(b) { return function(e) {
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return new fold(f,b,true,e); }; }; },
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foldp1 : function(f) { return function(e) {
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return new fold(f,function(x){return x;},true,e); }; },
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count : function(sig) {
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var incr = function(_){return function(c){return c+1;};};
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return new fold(incr,0,false,sig) },
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keepIf : function(pred) { return function(base) { return function(sig) {
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return new dropIf(function(x) { return !pred(x)},base,sig); }; }; },
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dropIf : function(pred) { return function(base) { return function(sig) {
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return new dropIf(pred,base,sig); }; }; },
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keepWhen : function(s) { return dropWhen(new lift(function(b){return !b;},[s])); },
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dropWhen : dropWhen,
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dropRepeats : function(s) { return new dropRepeats(s);},
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sampleOn : function(s1){return function(s2){return new sampleOn(s1,s2);};}
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};
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}(); |