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Array view instead of direct wasm memory access#53
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mike-kfed wants to merge 2 commits intorustwasm:masterfrom
Open
Array view instead of direct wasm memory access#53mike-kfed wants to merge 2 commits intorustwasm:masterfrom
mike-kfed wants to merge 2 commits intorustwasm:masterfrom
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| self.cells.as_ptr() | ||
| pub fn cells(&self) -> js_sys::Uint8Array { | ||
| unsafe { | ||
| let u8_cells = mem::transmute::<&Vec<Cell>, &Vec<u8>>(&self.cells); |
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I think this can avoid transmute here and instead cast the slice to pointer, convert the pointer, and construct a new slice from that:
let u8_cells: &[u8] = unsafe {
let ptr = self.cells.as_ptr() as *const u8;
let bytelen = self.cells.len() * std::mem::size_of::<Cell>();
std::slice::from_raw_parts(ptr, bytelen)
};
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Talking on discord I've learned that directly accessing wasm's linear memory to efficiently share data between the universes is not necessary anymore, because
js_sysnow has a view method for JavaScripts typed Arrays that does exactly that. To help other coders know about that feature, and more obviously show that this is unsafe code potentially, I adapted the code to use the view instead.