[bnbarak]

Per #1473, Im stated to implement destructuring assignment.
At this step, I will implement the array destructuring.

Please feel free to comment on the progress.

• I've read the contributing guidelines

[bnbarak]

Would love to hear some suggestion how to implement a "dummy" variable to avoid the double invocation

[dcodeIO]

We typically compile the Statements directly, i.e. not trying to "transpile" on the parser level, so we not only get a 1:1 roundtrip when serializing the AST again, but also do not have to deal with temporary AST nodes like the one that would be necessary here. Here, the compiler would typically implement a compileDestructuringAssignment method directly compiling to Binaryen IR, which may then use a temporary Wasm local.

[bnbarak]

Make sense. From what I hear I need to set the NodeKind to DESTRUCTED_VARIABLE. And then handle it in compileStatement() switch?

[bnbarak]

Or add a flag to the statement and keep the type to VARIABLE

[bnbarak]

@dcodeIO May I ask for your help with passing a test here. The same wat file array-destructuring.untouched.wat is passing on my local machine but fail the diff in the CI. I run Node version 14.16.1 on a macOS 10.13.6.

[MaxGraey]

AssemblyScript doesn't support undefined. Only null. And due to compiler support self-bootstrapping you should never use undefined even in compiler's codebase.

[bnbarak]

@MaxGraey @dcodeIO took me a while to get the tests to pass (needed to rebase - I guess the tests runs agains master merge not my current branch dah...).

I know you asked to use a local wasm variable to cache the callable expresionRef. Which I did, but during my experiments I implemented a local JS variable const _func = func(), a = _func[0]similar to how TS transpiles to ES5.

I can revert back to use a local wasm variable:

// part of "compileElementAccessExpression()" method in compilers.ts
let thisArg = this.compileExpressionMaybeCached(targetExpression, thisType, destructingKey); // Try to hit a cache result

Where compileExpressionMaybeCached uses scopedDummyLocal.

The only issues is that I got an error from the optimization test because "the Binaryen IR tree is not flat".

[github-actions]

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

[github-actions]

This PR has been automatically closed due to lack of recent activity, but feel free to reopen it as long as you merge in the main branch afterwards.