r3blrsutils

This library provides utility functions:

1. Functions to unwrap deeply nested objects inspired by Kotlin scope functions.
2. Non binary tree data structure inspired by memory arenas, that is thread safe and supports parallel tree walking.
3. Capabilities to make it easier to build TUIs (Text User Interface apps) in Rust.
4. And more.

💡 To learn more about this library, please read how it was built on developerlife.com.

• You can also read all the Rust content on developerlife.com here.
• The equivalent of this library is available for TypeScript and is called r3bl-ts-utils.

Usage

Please add the following to your Cargo.toml file:

toml [dependencies] r3bl_rs_utils = "0.5.6"

treememoryarena (non-binary tree data structure)

[Arena] and [MTArena] types are the implementation of a non-binary tree data structure that is inspired by memory arenas.

Here's a simple example of how to use the [Arena] type:

```rust use r3blrsutils::{ treememoryarena::{Arena, HasId, MTArena, ResultUidList}, utils::{styleprimary, styleprompt}, };

let mut arena = Arena::::new(); let node1value = 42 as usize; let node1id = arena.addnewnode(node1value, None); println!("{} {:#?}", styleprimary("node1id"), node1id); asserteq!(node1id, 0); ```

Here's how you get weak and strong references from the arena (tree), and tree walk:

```rust use r3blrsutils::{ treememoryarena::{Arena, HasId, MTArena, ResultUidList}, utils::{styleprimary, styleprompt}, };

let mut arena = Arena::::new(); let node1value = 42 as usize; let node1id = arena.addnewnode(node1value, None);

{ assert!(arena.getnodearc(&node1id).issome()); let node1ref = dbg!(arena.getnodearc(&node1id).unwrap()); let node1refweak = arena.getnodearcweak(&node1id).unwrap(); asserteq!(node1ref.read().unwrap().payload, node1value); asserteq!( node1refweak.upgrade().unwrap().read().unwrap().payload, 42 ); }

{ let nodeiddne = 200 as usize; assert!(arena.getnodearc(&nodeiddne).is_none()); }

{ let node1id = 0 as usize; let nodelist = dbg!(arena.treewalkdfs(&node1id).unwrap()); asserteq!(nodelist.len(), 1); asserteq!(node_list, vec![0]); } ```

Here's an example of how to use the [MTArena] type:

```rust use std::{ sync::Arc, thread::{self, JoinHandle}, };

use r3blrsutils::{ treememoryarena::{Arena, HasId, MTArena, ResultUidList}, utils::{styleprimary, styleprompt}, };

type ThreadResult = Vec; type Handles = Vec>;

let mut handles: Handles = Vec::new(); let arena = MTArena::::new();

// Thread 1 - add root. Spawn and wait (since the 2 threads below need the root). { let arenaarc = arena.getarenaarc(); let thread = thread::spawn(move || { let mut arenawrite = arenaarc.write().unwrap(); let root = arenawrite.addnewnode("foo".to_string(), None); vec![root] }); thread.join().unwrap(); }

// Perform tree walking in parallel. Note the lambda does capture many enclosing variable context. { let arenaarc = arena.getarenaarc(); let fnarc = Arc::new(move |uid, payload| { println!( "{} {} {} Arena weakcount:{} strongcount:{}", styleprimary("walkerfn - closure"), uid, payload, Arc::weakcount(&arenaarc), Arc::weakcount(&arenaarc) ); });

// Walk tree w/ a new thread using arc to lambda. { let threadhandle: JoinHandle = arena.treewalkparallel(&0, fnarc.clone());

let result_node_list = thread_handle.join().unwrap();
println!("{:#?}", result_node_list);

}

// Walk tree w/ a new thread using arc to lambda. { let threadhandle: JoinHandle = arena.treewalkparallel(&1, fnarc.clone());

let result_node_list = thread_handle.join().unwrap();
println!("{:#?}", result_node_list);

} } ```

📜 There are more complex ways of using [Arena] and [MTArena]. Please look at these extensive integration tests that put them thru their paces here.

utils

LazyMemoValues

This struct allows users to create a lazy hash map. A function must be provided that computes the values when they are first requested. These values are cached for the lifetime this struct. Here's an example.

```rust use std::sync::atomic::{AtomicUsize, Ordering::SeqCst}; use r3blrsutils::utils::LazyMemoValues;

// These are copied in the closure below. let arcatomiccount = AtomicUsize::new(0); let mut avariable = 123; let mut aflag = false;

let mut generatevaluefn = LazyMemoValues::new(|it| { arcatomiccount.fetchadd(1, SeqCst); avariable = 12; aflag = true; avariable + it });

asserteq!(arcatomiccount.load(SeqCst), 0); asserteq!(generatevaluefn.getref(&1), &13); asserteq!(arcatomiccount.load(SeqCst), 1); asserteq!(generatevaluefn.getref(&1), &13); // Won't regenerate the value. asserteq!(arcatomic_count.load(SeqCst), 1); // Doesn't change. ```

tty

This module contains a set of functions to make it easier to work with terminals.

The following is an example of how to use is_stdin_piped():

rust fn run(args: Vec<String>) -> Result<(), Box<dyn Error>> { match is_stdin_piped() { true => piped_grep(PipedGrepOptionsBuilder::parse(args)?)?, false => grep(GrepOptionsBuilder::parse(args)?)?, } Ok(()) }

The following is an example of how to use readline():

```rust use r3blrsutils::utils::{ printheader, readline, styledimmed, styleerror, styleprimary, style_prompt, };

fn makeaguess() -> String { println!("{}", Blue.paint("Please input your guess.")); let (bytesread, guess) = readline(); println!( "{} {}, {} {}", styledimmed("#bytes read:"), styleprimary(&bytesread.tostring()), styledimmed("You guessed:"), style_primary(&guess) ); guess } ```

safe_unwrap

Functions that make it easy to unwrap a value safely. These functions are provided to improve the ergonomics of using wrapped values in Rust. Examples of wrapped values are <Arc<RwLock<T>>, and <Option>. These functions are inspired by Kotlin scope functions & TypeScript expression based language library which can be found here on r3bl-ts-utils.

Here are some examples.

```rust use r3blrsutils::utils::{ callifsome, unwraparcreadlockandcall, unwraparcwritelockandcall, withmut, }; use r3blrsutils::utils::{ReadGuarded, WriteGuarded}; use r3blrsutils::{ arenatypes::HasId, ArenaMap, FilterFn, NodeRef, ResultUidList, WeakNodeRef, };

if let Some(parentid) = parentidopt { let parentnodearcopt = self.getnodearc(parentid); callifsome(&parentnodearcopt, &|parentnodearc| { unwraparcwritelockandcall(&parentnodearc, &mut |parentnode| { parentnode.children.push(newnode_id); }); }); } ```

Here's a list of functions that are provided:

• call_if_some()
• call_if_none()
• call_if_ok()
• call_if_err()
• with()
• with_mut()
• unwrap_arc_write_lock_and_call()
• unwrap_arc_read_lock_and_call()

Here's a list of type aliases provided for better readability:

• ReadGuarded<T>
• WriteGuarded<T>

color_text

ANSI colorized text https://github.com/ogham/rust-ansi-term helper methods. Here's an example.

```rust use r3blrsutils::utils::{ printheader, readline, styledimmed, styleerror, styleprimary, style_prompt, };

fn makeaguess() -> String { println!("{}", Blue.paint("Please input your guess.")); let (bytesread, guess) = readline(); println!( "{} {}, {} {}", styledimmed("#bytes read:"), styleprimary(&bytesread.tostring()), styledimmed("You guessed:"), style_primary(&guess) ); guess } ```

tui (experimental)

🚧 WIP - This is an experimental module that isn’t ready yet. It is the first step towards creating a TUI library that can be used to create sophisticated TUI applications. This is similar to Ink library for Node.js & TypeScript (that uses React and Yoga). Or kinda like tui built atop crossterm (and not termion).

Stability

🧑‍🔬 This library is in early development.

1. There are extensive integration tests for code that is production ready.
2. Everything else is marked experimental in the source.

Please report any issues to the issue tracker. And if you have any feature requests, feel free to add them there too 👍.