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- //
- // Sure, we can solve our async value problem with a global
- // variable. But this hardly seems like an ideal solution.
- //
- // So how do we REALLY get return values from async functions?
- //
- // The 'await' keyword waits for an async function to complete
- // and then captures its return value.
- //
- // fn foo() u32 {
- // return 5;
- // }
- //
- // var foo_frame = async foo(); // invoke and get frame
- // var value = await foo_frame; // await result using frame
- //
- // The above example is just a silly way to call foo() and get 5
- // back. But if foo() did something more interesting such as wait
- // for a network response to get that 5, our code would pause
- // until the value was ready.
- //
- // As you can see, async/await basically splits a function call
- // into two parts:
- //
- // 1. Invoke the function ('async')
- // 2. Getting the return value ('await')
- //
- // Also notice that a 'suspend' keyword does NOT need to exist in
- // a function to be called in an async context.
- //
- // Please use 'await' to get the string returned by
- // getPageTitle().
- //
- const print = @import("std").debug.print;
- pub fn main() void {
- var myframe = async getPageTitle("http://example.com");
- var value = ???
- print("{s}\n", .{value});
- }
- fn getPageTitle(url: []const u8) []const u8 {
- // Please PRETEND this is actually making a network request.
- _ = url;
- return "Example Title.";
- }
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