Is there an actionscript library providing a queuing system?
This system would have to allow me to pass the object, the function I want to invoke on it and the arguments, something like:
Queue.push(Object, function_to_invoke, array_of_arguments)
Alternatively, is it possible to (de-)serialize a function call? How would I evaluate the 'function_to_invoke' with the given arguments?
Thanks in advance for your help.
There's no specific queue or stack type data structure available in ActionScript 3.0 but you may be able to find a library (CasaLib perhaps) that provides something along those lines.
The following snippet should work for you but you should be aware that since it references the function name by string, you won't get any helpful compiler errors if the reference is incorrect.
The example makes use of the rest parameter which allows you to specify an array of arbitrary length as the arguments for your method.
function test(... args):void
{
trace(args);
}
var queue:Array = [];
queue.push({target: this, func: "test", args: [1, 2, "hello world"] });
queue.push({target: this, func: "test", args: ["apple", "pear", "hello world"] });
for (var i:int = 0; i < queue.length; i ++)
{
var queued:Object = queue[i];
queued.target[queued.func].apply(null, queued.args);
}
Sure, that works similar to JavaScript
const name:String = 'addChild'
, container:Sprite = new Sprite()
, method:Function = container.hasOwnProperty(name) ? container[name] : null
, child:Sprite = new Sprite();
if (method)
method.apply(this, [child]);
So a query method could look like:
function queryFor(name:String, scope:*, args:Array = null):void
{
const method:Function = scope && name && scope.hasOwnProperty(name) ? scope[name] : null
if (method)
method.apply(this, args);
}
Related
I was building my project for Windows and everything was working fine. Now I started building it in HTML5 and I'm getting an error with map iterators:
for (entryMap in mapStruct.map)
{
var array:Array<Dynamic> = entryMap;
var keyObj = getJSONField(array[0], mapStruct.keyType);
var valueObj = getJSONField(array[1], mapStruct.valueType);
map.set(keyObj, valueObj);
}
And I get this error:
Exception name: TypeError: mapStruct.map.iterator is not a function
My project was working fine for Windows, but I don't know what to do, I need to use map like this.
I was trying to guess what is mapStruct without any success.
It looks like your aren't looping on a map in the right way...
Let's see some examples:
var map = ["hello" => 1, "world" => 4];
for (value in map)
{
trace('value: $value');
}
returns:
value: 1
value: 4
Here you have the link to try it online.
On the other hand, if you want to get either key and value, you should iterate it this way:
var map = ["hello" => 1, "world" => 4];
for (key in map.keys())
{
trace('key: $key value: ${map[key]}');
}
* Note the keys method call
And it returns:
key: hello value: 1
key: world value: 4
Here's the 'Try Haxe' link for it
if I knew which type mapStruct is, I'd probably help you more
While exploring the documented example raised in this perl6 question that was asked here recently, I found that the final implementation option - (my interpretation of the example is that it provides three different ways to do something) - doesn't work. Running this;
class HTTP::Header does Associative {
has %!fields handles <iterator list kv keys values>;
sub normalize-key ($key) { $key.subst(/\w+/, *.tc, :g) }
method EXISTS-KEY ($key) { %!fields{normalize-key $key}:exists }
method DELETE-KEY ($key) { %!fields{normalize-key $key}:delete }
method push (*#_) { %!fields.push: #_ }
multi method AT-KEY (::?CLASS:D: $key) is rw {
my $element := %!fields{normalize-key $key};
Proxy.new(
FETCH => method () { $element },
STORE => method ($value) {
$element = do given $value».split(/',' \s+/).flat {
when 1 { .[0] } # a single value is stored as a string
default { .Array } # multiple values are stored as an array
}
}
);
}
}
my $header = HTTP::Header.new;
say $header.WHAT; #-> (Header)
$header<Accept> = "text/plain";
$header{'Accept-' X~ <Charset Encoding Language>} = <utf-8 gzip en>;
$header.push('Accept-Language' => "fr"); # like .push on a Hash
say $header<Accept-Language>.perl; #-> $["en", "fr"]
... produces the expected output. Note that the third last line with the X meta-operator assigns a literal list (built with angle brackets) to a hash slice (given a flexible definition of "hash"). My understanding is this results in three seperate calls to method AT-KEY each with a single string argument (apart from self) and therefore does not exersise the default clause of the given statement. Is that correct?
When I invent a use case that excersises that part of the code, it appears to fail;
... as above ...
$header<Accept> = "text/plain";
$header{'Accept-' X~ <Charset Encoding Language>} = <utf-8 gzip en>;
$header{'Accept-Language'} = "en, fr, cz";
say $header<Accept-Language>.perl; #-> ["en", "fr", "cz"] ??
# outputs
(Header)
This Seq has already been iterated, and its values consumed
(you might solve this by adding .cache on usages of the Seq, or
by assigning the Seq into an array)
in block at ./hhorig.pl line 20
in method <anon> at ./hhorig.pl line 18
in block <unit> at ./hhorig.pl line 32
The error message provides an awesome explanation - the topic is a sequence produced by the split and is now spent and hence can't be referenced in the when and/or default clauses.
Have I correctly "lifted" and implemented the example? Is my invented use case of several language codes in the one string wrong or is the example code wrong/out-of-date? I say out-of-date as my recollection is that Seq's came along pretty late in the perl6 development process - so perhaps, this code used to work but doesn't now. Can anyone clarify/confirm?
Finally, taking the error message into account, the following code appears to solve the problem;
... as above ...
STORE => method ($value) {
my #values = $value».split(/',' \s+/) ;
$element = do given #values.flat {
when 1 { $value } # a single value is stored as a string
default { #values } # multiple values are stored as an array
}
}
... but is it an exact equivalent?
That code works now (Rakudo 2018.04) and prints
$["en", "fr", "cz"]
as intended. It was probably a bug which was eventually solved.
Say I have this method of a RuleFactory:
public function makeFromArray($rules)
{
$array = [];
foreach ($rules as $rule) {
$array[] = new Rule($rule[0], $rule[1]);
}
return $array;
}
I want to test that the return array contains Rule elements. Here is my test:
function it_should_create_multiple_rules_at_once()
{
$rules = [
['required', 'Please provide your first name'],
['alpha', 'Please provide a valid first name']
];
$this->makeFromArray($rules)->shouldHaveCount(2);
$this->makeFromArray($rules)[0]->shouldBeInstanceOf('Rule');
$this->makeFromArray($rules)[1]->shouldBeInstanceOf('Rule');
}
But this does not work, it throws an error in PHPSpec.
The strange thing is that I can do this just fine on other methods that return arrays, but for some reason I cannot do that here.
The error I get is this:
! it should create multiple rules at once
method [array:2] not found
How do I test the contents of this return array, WITHOUT creating my own inline matcher?
Your method accepts a single rule, not all of them. The spec should be:
$this->makeFromArray($rules)->shouldHaveCount(2);
$this->makeFromArray($rules[0])[0]->shouldBeAnInstanceOf('Rule');
$this->makeFromArray($rules[1])[1]->shouldBeAnInstanceOf('Rule');
Or, to avoid multiple calls:
$rules = $this->makeFromArray($rules);
$rules->shouldHaveCount(2);
$rules[0]->shouldBeAnInstanceOf('Rule');
$rules[1]->shouldBeAnInstanceOf('Rule');
Still, the most readable version would be the one leveraging a custom matcher:
$rules->shouldHaveCount(2);
$rules->shouldContainOnlyInstancesOf('Rule');
so I am using express within a node-app. As my app is getting bigger I want to put my routes into extra files. I seem to be able to get hold of the bugDB if I just get rid of the intermediate get object. But I can't access the bugDB in the inner object. Any suggestions? Maybe there is even a more nice code pattern for how to accomplish this more elegantly.
I would appreachate your help. Thanks in advance. (As I am not a native speaker I couldn't find others with a similar problem, if you know how to phrase the question better, please show me the way :) )
BUGROUTER.COFFEE
class BugsRouter
constructor: (#bugDB)-> // instance-variable with databaselink
return
get:{
allBugs: (req, res)=>
console.log "db", #bugDB // this gives me undefined
// is "this" in the get context?
#bugDB.allDocs {include_docs: true}, (err, response)->
res.json 200, response
}
module.exports = BugsRouter
SERVER.COFFEE
BugsRouter = require "./routes/BUGROUTER"
bugsRouter = new BugsRouter(bugDB)
console.log bugsRouter.bugDB # this is working
app.get "/bugs/all", bugsRouter.get.allBugs
Sub-objects don't work like that. When you say this:
class C
p:
f: ->
Then p is just a plain object that happens to be a property on C's prototype, it will have no special idea of what # should be inside f. And if you try to use a fat-arrow instead:
class C
p:
f: =>
then you're accidentally creating a namespaced class function called f so # will be C when f is called. In either case, saying:
c = new C
c.p.f()
is the same as:
c = new C
p = c.p
p.f()
so f will be called in the context of p rather than c.
You can get around this if you don't mind manually binding the functions inside get when your constructor is called:
constructor: (#bugDB) ->
#get = { }
for name, func of #constructor::get
#get[name] = func.bind(#)
This assumes that you have Function.bind available. If you don't then you can use any of the other binding techniques (_.bind, $.proxy, ...). The #get = { } trick is needed to ensure that you don't accidentally modify the prototype's version of #get; if you're certain that you'll only be creating one instance of your BugsRouter then you could use this instead:
constructor: (#bugDB) ->
for name, func of #get
#get[name] = func.bind(#)
to bind the functions inside the prototype's version of get rather than the instance's local copy.
You can watch this simplified demo to see what's going on with # in various cases, keep an eye on the #flag values to see the accidental prototype modification caused by not using #get = { } and #constructor::get:
class C1
get:
f: -> console.log('C1', #)
class C2
get:
f: => console.log('C2', #)
class C3
constructor: ->
#flag = Math.random()
for name, func of #get
#get[name] = func.bind(#)
get:
f: -> console.log('C3', #)
class C4
constructor: ->
#flag = Math.random()
#get = { }
for name, func of #constructor::get
#get[name] = func.bind(#)
get:
f: -> console.log('C4', #)
for klass in [C1, C2, C3, C3, C4, C4]
o = new klass
o.get.f()
Live version of the above: http://jsfiddle.net/ambiguous/8XR7Z/
Hmm, seems like I found a better solution after all:
class Test
constructor: ->
#testVariable = "Have a nice"
return
Object.defineProperties #prototype,
get:
enumerable :true
get:->
{
day: => #testVariable + " day"
week: => #testVariable + " day"
}
console.log (new Test()).get.day()
This allows me to call (new Test()).get.day() the way I wanted.
Live version at: JSFiddle
So I want to allow the user to conditionally turn columns on/off in a Cardboard app I built. I have two problems.
I tried using the 'columns' attribute in the config but I can't seem to find a default value for it that would allow ALL columns to display(All check boxes checked) based on the attribute, ie. the default behavior if I don't include 'columns' in the config object at all (tried null, [] but that displays NO columns).
So that gets to my second problem, if there is no default value is there a simple way to only change that value in the config object or do I have to encapsulate the entire variable in 'if-else' statements?
Finally if I have to manually build the string I need to parse the values of an existing custom attribute (a drop list) we have on the portfolio object. I can't seem to get the rally.forEach loop syntax right. Does someone have a simple example?
Thanks
Dax - Autodesk
I found a example in the online SDK from Rally that I could modify to answer the second part (This assumes a custom attribute on Portfolio item called "ADSK Kanban State" and will output values to console) :
var showAttributeValues = function(results) {
for (var property in results) {
for (var i=0 ; i < results[property].length ; i++) {
console.log("Attribute Value : " + results[property][i]);
}
}
};
var queryConfig = [];
queryConfig[0] = {
type: 'Portfolio Item',
key : 'eKanbanState',
attribute: 'ADSK Kanban State'
};
rallyDataSource.findAll(queryConfig, showAttributeValues);
rally.forEach loops over each key in the first argument and will execute the function passed as the second argument each time.
It will work with either objects or arrays.
For an array:
var array = [1];
rally.forEach(array, function(value, i) {
//value = 1
//i = 0
});
For an object:
var obj = {
foo: 'bar'
};
rally.forEach(obj, function(value, key) {
//value = 'bar'
//key = 'foo'
});
I think that the code to dynamically build a config using the "results" collection created by your query above and passed to your sample showAttributeValues callback, is going to look a lot like the example of dynamically building a set of Table columns as shown in:
Rally App SDK: Is there a way to have variable columns for table?
I'm envisioning something like the following:
// Dynamically build column config array for cardboard config
var columnsArray = new Array();
for (var property in results) {
for (var i=0 ; i < results[property].length ; i++) {
columnsArray.push("'" + results[property][i] + "'");
}
}
var cardboardConfig = {
{
attribute: 'eKanbanState',
columns: columnsArray,
// .. rest of config here
}
// .. (re)-construct cardboard...
Sounds like you're building a neat board. You'll have to provide the board with the list of columns to show each time (destroying the old board and creating a new one).
Example config:
{
attribute: 'ScheduleState'
columns: [
'In-Progress',
'Completed'
]
}