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Search - "deserialization"
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PHP arrays.
The built-in array is also an hashmap. Actually, it's always a hashmap, but you can append to it without specifying indexes and PHP will use consecutive integers. Its performance characteristics? Who knows. Oh, and only strings, ints and null are valid keys.
What's the iteration order for arrays if you use them as hashmaps (string keys)? Well, they have their internal order. So it's actually an ordered hashmap that's being called an array. And you can produce an array which has only integer keys starting with 0, but with non-sequential internal (iteration) order.
This array weirdness has some non-trivial implications. `json_encode` (serializes argument to JSON) assumes an array corresponds to a JSON array if its keys are consecutive integers in increasing order starting with 0, otherwise the array becomes a JSON object. `array_filter` (filters arrays/hashmaps using callback predicate) preserves keys, so it will punch holes in the int key sequence if non-last items are removed, thus turning arrays into hashmaps and changing your JSON structure if you forget to discard keys before serialization.
You may wonder how JSON deserialization works, then? There's a special class for deserialized JSON objects, `stdClass`. It's basically a hashmap too, but it's an object, not an array, and all functions that would normally accept arrays won't work with it. So basically its only use is JSON (de)serialization. You can even cast arrays to objects, producing `stdClass`.
Bonus PHP trivia:
Many functions return nonsensical values. `preg_match`, the regex matching function, returns 1 for success, 0 for no matches and false for malformed regular expression. PHP supports exceptions, so it could just throw one on errors. It would even make more sense to return true, false and null for these three cases. But no, 1, 0 and false. And actual matches are returned by output arg.
`array_walk_recursive`, a function supposed to recursively apply callback to each element of an array. That's what docs say. It actually applies it to leafs only. It will also silently accept object instead of array and "walk" it, but without recursing into deeper objects.
Runtime type enforcing is supported for function arguments and returned values. You can use scalar types, classes, array, null and a few special keywords. There's also a `mixed` keyword, which is used in docs and means "anything". It's syntactically valid, the parser will accept it, but it matches no values in runtime. Calling such function will always cause a runtime error.
Strings can be indexed with negative integers. Arrays can't.
ReflectionClass::newInstanceWithoutConstructor: "Creates a new class instance without invoking the constructor". This one needs no commentary.
`array_map` is pretty self-explanatory if you call it with a callback and an array. Or if you provide more arrays of equal length via varargs, callback will be called with more arguments, one from each array. Makes sense so far. Now, you can also call `array_map` with null instead of callback. In that case it treats provided arrays as rows of a matrix and returns that matrix, transposed.5 -
FUUCCK! These two lines of code just cost me 6 hours of debugging... At least I learned I need to fix my Deserialization code too.
servicePassword: this.APIUsername,
serviceUser: this.APIPassword -
So I figure since I straight up don't care about the Ada community anymore, and my programming focus is languages and language tooling, I'd rant a bit about some stupid things the language did. Necessary disclaimer though, I still really like the language, I just take issue with defense of things that are straight up bad. Just admit at the time it was good, but in hindsight it wasn't. That's okay.
For the many of you unfamiliar, Ada is a high security / mission critical focused language designed in the 80's. So you'd expect it to be pretty damn resilient.
Inheritance is implemented through "tagged records" rather than contained in classes, but dispatching basically works as you'd expect. Only problem is, there's no sealing of these types. So you, always, have to design everything with the assumption that someone can inherit from your type and manipulate it. There's also limited accessibility modifiers and it's not granular, so if you inherit from the type you have access to _everything_ as if they were all protected/friend.
Switch/case statements are only checked that all valid values are handled. Read that carefully. All _valid_ values are handled. You don't need a "default" (what Ada calls "when others" ). Unchecked conversions, view overlays, deserialization, and more can introduce invalid values. The default case is meant to handle this, but Ada just goes "nah you're good bro, you handled everything you said would be passed to me".
Like I alluded to earlier, there's limited accessibility modifiers. It uses sections, which is fine, but not my preference. But it also only has three options and it's bizarre. One is publicly in the specification, just like "public" normally. One is in the "private" part of the specification, but this is actually just "protected/friend". And one is in the implementation, which is the actual" private". Now Ada doesn't use classes, so the accessibility blocks are in the package (namespace). So guess what? Everything in your type has exactly the same visibility! Better hope people don't modify things you wanted to keep hidden.
That brings me to another bad decision. There is no "read-only" protection. Granted this is only a compiler check and can be bypassed, but it still helps prevent a lot of errors. There is const and it works well, better than in most languages I feel. But if you want a field within a record to not be changeable? Yeah too bad.
And if you think properties could fix this? Yeah no. Transparent functions that do validation on superficial fields? Nah.
The community loves to praise the language for being highly resilient and "for serious engineers", but oh my god. These are awful decisions.
Now again there's a lot of reasons why I still like the language, but holy shit does it scare me when I see things like an auto maker switching over to it.
The leading Ada compiler is literally the buggiest compiler I've ever used in my life. The leading Ada IDE is literally the buggiest IDE I've ever used in my life. And they are written in Ada.
Side note: good resilient systems are a byproduct of knowledge, diligence, and discipline, not the tool you used. -
v0.0005a (alpha)
- class support added to lua thanks to yonaba.
- rkUIs class created
- new panel class
- added drawing code for panel
- fixed bug where some sides of the UI's border were failing to drawing (line rendering quark)
v0.0014a (alpha) 11.30.2023 (~2 hours)
- successfully retrieving basic data from save folder, load text into lua from files
- added 'props' property to Entity class
- added a props table to control what gets serialized and what doesn't
- added a save() base method for instances (has to be overridden to be useful beyond the basics)
- moved the lume.serialize() call into the :save() method on the base entity class itself
- serialized and successfully saved an entities property table.
- fixed deserializion bugs involving wrong indexes (savedata[1] not savedata[2])
- moved deserialization from temp code, into line loading loop itself (assuming each item is on one line)
- deser'd test data, and init()'d new player Entity using the freshly-loaded data, and displayed the entity sprite
All in all not a bad session. Understanding filing handling and how to interact with the directory system was the biggest hurdle I was worried about for building my tools.
Next steps will be defining some basic UI elements (with overridable draw code), and then loading and initializing the UI from lua or json.
New projects can be set as subfolders folders in appdata, using 'Setidentity("appname/projectname") to keep things clean.
I'm not even dreading writing basic syntax highlighting!
Idea is to dogfood the whole process. UI is in-engine rendered just like you might see with godot, unity, or gamemaker, that way I have maximum flexibility to style it the way I want. I'm familiar enough with constructing from polygons, on top of stenciling, on top of nine-slicing, on top of existing tweening and special effects, that I can achieve exactly what I want.
Idea is to build a really well managed asset pipeline. Stencyl, as 'crappy' as it appeared, and 'for education' was a master class in how to do things the correct way, it was just horribly bloated while doing it.
Logical tilesets that you import, can rearrange through drag-n-drop, assign custom tile shapes to, physics materials, collisions groups, name, add tag data to, all in one editor? Yes please.
Every other 2D editor is basic-bitch, has you importing images, and at most generates different scales and does the slicing for you.
Code editor? Everything behavior was in a component, with custom fields. All your code goes into a list of events, which you can toggle on and off with a proper toggle button, so you can explicitly experiment, instead of commenting shit out (yes git is better, but we're talking solo amateurs here, they're not gonna be using git out the gate unless they already know what they're doing).
Components all have an image assignable to identify them, along with a description field, and they're arranged in a 2d grid for easy browsing, copying, modifying.
The physics shape editor, the animation editor, the map editor, all of it was so bare bones and yet had things others didn't.
I want that, except without the historic ties to flash, without the overhead of java, and with sexier fucking in-engine rendering of the UI and support for modding and in-engine custom tools.
Not really doing it for anyone except myself, and doubt I'll get very far, but since I dropped looking for easy solutions, I've just been powering through all the areas I don't understand and doing the work.
I rediscovered my love of programming after 3-4 years of learning to hate it, and things are looking up.2 -
I think the Golang serialization API is utter garbage.
By convention it usually looks like this,
MarshalFormat() ([]byte,error)
UnmarshalFormat([]byte) error
This means that all serialization and deserialization is done on, heap allocated, in memory buffers ( technically also mmaped files, but thats not cross platform).
As the Go GC is ruthlessly optimized for minimum latency, this can potentially cause memory leaks in long running applications.
I think we need a new serialization API that looks more like
SerializeFormat(io.Writer) error
DeserializeFormat(io.Reader) error3 -
The documentation of scala akka http may be just gibberish as far as I am concerned. You would think that hooking into the marshalling process (aka de/serialization) would be straight forward, I've dealt with similar problems before and solved it.
I have an object, it should be transformed into a Json and vice versa. Should be easy as pie.
Not with scala and akka-http. The docs tell you how to achieve something in dozen different ways yet lack a complete example. My first custom marshaller I created in a "marshall" package in my! namespace, but it was breaking scala compilation due to some black magic.
It's not clear how when and why marshallers are added, they just somehow are. Why do I have to deal with entity marshallers vs response marshallers. I just want each instance of a certain type to be transformed into a specific Json presentation.
Asking on stackoverflow also only yields in incomplete hints of "just do boargh" presupposing certain knowledge while sounding borderline condescending.
Currently, I just want to burn the project and rebuild it with fucking PHP. Flame all you want, at least I would get things done and the JMS serializer library has decent documentation and it works in an expected way.
Akka-http, combined with Scala, looks from my current rage-driven perspective like a solution worse than the problem. -
Okay, so I had an object consisting of tables (basically classes) and structs (classes with only scalars as their properties).
I was about to serialize the object with vectors of classes and structs and wrote some nice tests for it wondering why they fail to validate the data after deserialization and why I only got garbage for the vectors of structs whilst the tables worked just fine.
Turns out there is an undocumented function called CreateVectorOfStructs which shall be used for structs instead of the regular CreateVector ...
There go three hours of blaming memory issues and running Valgrind over and over again ...