In assemblyscript,Is there a way to check the type of a value in wasm which has been loaded by assemblyscript, example:i32?

[chooaya]

-1
In the capture image,main.ts is a assemblyscript

assembly/main.ts (assemblyscript)

declare function sayHello(): void;

sayHello()

export function add(x: i32, y: i32): i32 {
 return x + y;
}

export function getTypeOf():string {
 let x:i32 = 12;
 return typeof x;
}
export function teste(): string {
 let x = "ZZZZZZZZZZZZ"
 return x;
}

but the code

export function getTypeOf():string{
 let x:i32 = 12;
 return typeof x;
}

src/main.js

(async()=>{
 let buffer = await fetch("../out/main.wasm");
 let arrayBuffer = await buffer.arrayBuffer();
 let lib = instantiateBuffer(arrayBuffer,{
 main:{
 sayHello(){
 console.log("Hello from WebAssembly!");
 }
 },
 env:{
 abort(_msg, _file, line, column){
 console.error("abort called at main.ts:" + line + ":" + column);
 }
 },
 });
 document.getElementById("container").textContent = "Result: " + lib.add(19, 23) 
 + " Type:" + lib.__getString(lib.getTypeOf()) 
 + " teste:" + lib.__getString(lib.teste()) ;
})();

lib.getTypeOf() return a ptr of a string,so I use lib.__getString(ptr) to convert ptr to string.but a value is "number",not the "i32"

### Issue: The Expected value of This Function is "i32",but actuality the result is "number"

I added a assemblyscript loader by download from 「 https://raw.githubusercontent.com/AssemblyScript/assemblyscript/master/lib/loader/index.js 」,and rename the to loader.js and put the file to folder src.

### In assemblyscript,we have i32 A 32-bit signed integer,if we load this wasm ,so we can check the type of i32?If cannot check i32 by assemblyscript,is there another way to check the value of wasm ?
wasm-project201910070050.zip

PS:
This days ,I found the https://github.com/AssemblyScript/assemblyscript/tree/master/lib/parse
,but I don`t know the detail about the parse,is this parse can check type the type of i32?

[magic-akari]

Check this out: microsoft/TypeScript#33290

[chooaya]

Check this out: microsoft/TypeScript#33290

Thank you.But my quesiton is about the i32 type in assemblyscript,is there a Connection between this issue and the microsoft/TypeScript#33290 ?

[MaxGraey]

Javascript support only numbers (which 64-bit double floats by standard, internally browsers also support Smi but not in this case). All integers during pass from AssemblyScript to javascript and vise versa convert to numbers implicitly, so i32, u64, f32 and etc converts to number (f64) on javascript side.

[dcodeIO]

typeof is more of a compatibility feature, but there's also nameof<T>() that can be used to obtain a more AssemblyScript-y name.

[chooaya]

Javascript support only numbers (which 64-bit double floats by standard, internally browsers also support Smi but not in this case). All integers during pass from AssemblyScript to javascript and vise versa convert to numbers implicitly, so i32, u64, f32 and etc converts to number (f64) on javascript side.

assembly/main.ts is a assemblyscript,so In assemblyscript,i32,u64,f32 is different type,so If typeof can not be used for check the difference,difference check is necessary.

[chooaya]

typeof is more of a compatibility feature, but there's also nameof<T>() that can be used to obtain a more AssemblyScript-y name.

Thank you. Would you like to share the link of the nameof() API?

[dcodeIO]

Was missing in the docs, but added it here: https://docs.assemblyscript.org/basics/environment#utility

[chooaya]

Thank you, Everyone, so is it a way to check the type of a value in wasm ?

[dcodeIO]

If all you need is to evaluate differences between types, the recommended way to do so is to use builtins like isInteger<T>, isString<T> etc. (see). These differ from what is available in JS where everything is dynamic, in that these are compile-time static checks that the compiler can utilize to eliminate untaken branches (see).

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[mesozoic-technology]

So how does one call nameof? My program isn't compiling when I try to call it - nameoof<t>(whatIWantToFindTheNameOf)

the docs do not mention how to actually invoke it.

[jerrygreen]

I don’t see any useful usage in nameof but I would really like to use typeof. That’s unfortunate I can’t use such fundamental function as typeof. If it doesn’t require GC (it doesn’t seem to), then I’m not even sure why it’s still not there for all these past years