language-servers/roc
1
0
Fork 0
mirror of https://github.com/roc-lang/roc.git synced 2025-09-27 13:59:08 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 6

wasm_interp: comment to clarify the two CLI systems

Browse source
This commit is contained in:
Brian Carroll 2022-12-06 09:38:08 +00:00
parent df5baf4211
commit c7a75bf770
No known key found for this signature in database
GPG key ID: 5C7B2EC4101703C0
1 changed files with 13 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

14
crates/wasm_interp/src/instance.rs
View file

@ -151,8 +151,20 @@ impl<'a, I: ImportDispatcher> Instance<'a, I> {
fn_name: &str,
arg_strings: &'a [&'a String],
) -> Result<Option<Value>, String> {
let arg_type_bytes = self.prepare_to_call_export(module, fn_name)?;
// We have two different mechanisms for handling CLI arguments!
// 1. Basic numbers:
// e.g. `roc_wasm_interp fibonacci 12`
// Below, we check if the called Wasm function takes numeric arguments and, if so, parse them from the CLI.
// This is good for low-level test cases, for example while developing this interpreter.
// 2. WASI:
// POSIX-style array of strings. Much more high-level and complex than the "basic" version.
// The WASI `_start` function itself takes no arguments (its Wasm type signature is `() -> nil`).
// The program uses WASI syscalls to copy strings into Wasm memory and process them.
// But that happens *elsewhere*! Here, `arg_strings` is ignored because `_start` takes no arguments.
// Implement the "basic numbers" CLI
// Check if the called Wasm function takes numeric arguments, and if so, try to parse them from the CLI.
let arg_type_bytes = self.prepare_to_call_export(module, fn_name)?;
for (value_str, type_byte) in arg_strings
.iter()
.skip(1) // first string is the .wasm filename