Hi,
I'm a bit puzzled by "scope" of "use". The following program doesn't compile, the line
use rayon::iter::ParallelIterator; must be placed before usage of par_iter() and in the top section.
The only dependency is
rayon = "1.2.1"
Code:
use rayon::iter::IntoParallelRefIterator;
use std::fs;
use std::fs::DirEntry;
use std::path::{Path, PathBuf};
use std::sync::{Arc, Mutex};
#[derive(Debug)]
struct Content {
files: Vec<PathBuf>,
dirs: Vec<PathBuf>,
}
impl Content {
fn build(files: Vec<PathBuf>, dirs: Vec<Content>) -> Content {
let mut f = vec![];
let mut d = vec![];
f.extend_from_slice(&files);
for c in dirs {
f.extend_from_slice(&c.files);
d.extend_from_slice(&c.dirs);
}
Content { files: f, dirs: d }
}
}
fn main() {
let content = get_file_list(PathBuf::from("."));
println!(
"dirs: {}, files: {}",
content.dirs.len(),
content.files.len()
);
}
fn get_file_list(path: PathBuf) -> Content {
let files = fs::read_dir(&path)
.map_err(|e| format!("Unable to read dir: {}", e))
.unwrap();
let list: Vec<DirEntry> = files
.into_iter()
.map(|r| r.expect(format!("Unable to read dir").as_str()))
.collect();
//use rayon::iter::ParallelIterator; // Uncomment this line to build successfully
let files: Vec<PathBuf> = list
.par_iter()
.filter(|e| e.file_type().expect("cant get type").is_file())
.map(|file| file.path())
.collect();
let dirs: Vec<Content> = list
.par_iter()
.filter(|e| e.file_type().expect("cant get type").is_dir())
.map(|dir| {
let mut c = get_file_list(dir.path());
c.dirs.push(dir.path());
c
})
.collect();
Content::build(files, dirs)
}