Cargo.toml

[package]
name = "preferential_attachment"
version = "0.1.0"

[dependencies]
rand = "0.3"

lib.rs

mod model;

main.rs

extern crate preferential_attachment;

use preferential_attachment::model;

fn main() {
    println!("{}", model::hello());
}

model.rs

extern crate rand;

use rand::Rng;

pub fn hello() -> &'static str {
    "hi"
}

pub struct Graph {
    a: i32,
    c: i32,
    n: i32,
    edges: Vec<i32>
}

pub fn build_graph(a: i32, c: i32, n: i32) -> Graph {
    let phi = (c / (c + a)) as f32;
    let mut rng = rand::thread_rng();
    for _ in 0..n {
        if rng.gen::<f32>() < phi {

        } else {

        }
    }
    Graph { a: a, c: c, n: n, edges: Vec::new() }
}

$ cargo build
   Compiling libc v0.2.17
   Compiling rand v0.3.14
   Compiling preferential_attachment v0.1.0 (file:///Users/pedro/Documents/Code/network-models/hw6/preferential_attachment)
error[E0432]: unresolved import `rand::Rng`
 --> src/model.rs:3:5
  |
3 | use rand::Rng;
  |     ^^^^^^^^^ Did you mean `self::rand`?

error: no method named `gen` found for type `model::rand::ThreadRng` in the current scope
  --> src/model.rs:20:16
   |
20 |         if rng.gen::<f32>() < phi {
   |                ^^^
   |
   = help: items from traits can only be used if the trait is in scope; the following trait is implemented but not in scope, perhaps add a `use` for it:
   = help: candidate #1: `use model::rand::Rng`

error: aborting due to previous error

error: Could not compile `preferential_attachment`.

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