Ekdohibs
/
zig
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

docs: wasm

master
Shritesh Bhattarai 2019-05-19 19:26:10 -07:00
parent 1c73c08298
commit 3b6fc3fdc7
1 changed files with 27 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
doc/langref.html.in
View File

@ -8434,6 +8434,8 @@ fn concat(allocator: *Allocator, a: []const u8, b: []const u8) ![]u8 {
</li>
<li>Are you linking libc? In this case, {#syntax#}std.heap.c_allocator{#endsyntax#} is likely
the right choice, at least for your main allocator.</li>
<li>Are you building for WebAssembly? In this case, {#syntax#}std.heap.wasm_allocator{#endsyntax#} is likely
the only possible choice for your main allocator.</li>
<li>
Is the maximum number of bytes that you will need bounded by a number known at
{#link|comptime#}? In this case, use {#syntax#}std.heap.FixedBufferAllocator{#endsyntax#} or
@ -8964,8 +8966,12 @@ all your base are belong to us</code></pre>
{#header_close#}
{#header_close#}
{#header_open|WebAssembly#}
<p>Zig supports building for WebAssembly out of the box. There is also a specialized {#syntax#}std.heap.wasm_allocator{#endsyntax#}
memory allocator for WebAssembly environments.</p>
{#header_open|Freestanding#}
{#code_begin|lib|wasm#}
<p>For embedded environments like the web browser and nodejs, build as a library using the freestanding OS target.
Here's an example of running Zig code compiled to WebAssembly with nodejs.</p>
{#code_begin|lib|math#}
{#target_wasm#}
extern fn print(i32) void;
@ -8974,7 +8980,22 @@ export fn add(a: i32, b: i32) void {
}
{#code_end#}
{#header_close#}
<p class="file">test.js</p>
<pre><code>const fs = require('fs');
const source = fs.readFileSync("./math.wasm");
const typedArray = new Uint8Array(source);
WebAssembly.instantiate(typedArray, {
env: {
print: (result) =&gt; { console.log(`The result is ${result}`); }
}}).then(result =&gt; {
const add = result.instance.exports.add;
add(1, 2);
});</code></pre>
<pre><code>$ node test.js
The result is 3</code></pre>
{#header_open|WASI#}
<p>Zig's support for WebAssembly System Interface (WASI) is under active development. Example of using the standard library and reading command line arguments:</p>
{#code_begin|exe|wasi#}
{#target_wasi#}
const std = @import("std");
@ -8988,6 +9009,10 @@ pub fn main() !void {
}
}
{#code_end#}
<pre><code>$ wasmer run wasi.wasm 123 hello
0: wasi.wasm
1: 123
2: hello</code></pre>
{#header_close#}
{#header_close#}
{#header_open|Targets#}
@ -9228,6 +9253,7 @@ Available libcs:
s390x-linux-musl
sparc-linux-gnu
sparcv9-linux-gnu
wasm32-freestanding-musl
x86_64-linux-gnu
x86_64-linux-gnux32
x86_64-linux-musl</code></pre>