Yinon Burgansky
Yinon Burgansky
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MModular
Created by Yinon Burgansky on 3/29/2024 in #questions
Returning a reference from a factory
I know that reference and lifetimes are still being worked on, but I was wondering if it will be possible to return a reference from a factory function, e.g.: 
fn some_factory() -> Reference[String]:
    var build_string = "Hello" # initially lifetime is bounded to the local variable in the function scope
    return Reference(build_string) # extend the lifetime since the string reference is returned outside the function scope

fn main():
    var x = some_factory() # lifetime of the string is now bounded to lifetime of x 
    print(x) # prints "Hello"
    # x containing the string is freed here
fn some_factory() -> Reference[String]:
    var build_string = "Hello" # initially lifetime is bounded to the local variable in the function scope
    return Reference(build_string) # extend the lifetime since the string reference is returned outside the function scope

fn main():
    var x = some_factory() # lifetime of the string is now bounded to lifetime of x 
    print(x) # prints "Hello"
    # x containing the string is freed here
I think that it's not possible in Rust, it would be nice to know if something like this will be possible in Mojo.
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