Write docs and clean up

README.md

@@ -3,57 +3,84 @@
 High-level programming language with effortless concurrency, automatic memory management and type
 safety.
 
-## Concepts
+Dust is a work in progress. Because it aims to deliver a high level of safety, extensive testing
+is required. The language is still in the design phase, and the syntax is subject to change.
 
-Dust is heavily influenced by Rust, but aims to be more high-level and easier to use. Its approach
+## Usage
-to safety is similar in that it will refuse to run programs with issues that can be caught by
+
-static analysis. However, Dust is not compiled and while performance is a concern, it is less
+The Dust command line tool can be used to run Dust programs. It is not yet available outside of
-important than safety and ease of use.
+this repository.
+
+```sh
+cargo run --package dust-shell -- examples/hello_world.ds
+```
+
+```sh
+cargo run --package dust-shell -- -c "'Hello my name is ' + read_line() + '!'"
+```
+
+Dust is easily embedded in another program. You can run a dust program of any size or complexity
+with a single function.
+
+```rust
+use dust_lang::{run, Value};
+
+fn main() {
+    let code = "
+        x = 'Dust'
+        y = ' is awesome!'
+
+        write_line(x + y)
+
+        42
+    ";
+
+    let result = dust.run(code).unwrap();
+
+    assert_eq!(result, Ok(Some(Value::integer(42))));
+}
+```
+
+## Concepts
 
 ### Effortless Concurrency
 
-Rust promises *fearless* concurrency, and Dust takes it a step further by making concurrency as
+Dust takes it a step further by making concurrency as effortless as possible. Dust is organized
-*effortless* as possible. Dust is organized into **statements**, and any sequence of statements can
+into **statements**, and any sequence of statements can be run concurrently by simply adding the
-be run concurrently by simply adding the `async` keyword before the block of statements.
+`async` keyword before the block of statements.
 
-```dust
+```rust
-# This function will count from 0 to 9, sleeping for an increasing amount of
+// Counts from 0 to 9, sleeping for an increasing amount of time between each.
-# time between each number.
+count_slowly = fn (multiplier: int) {
-count_slowly = fn (
-	multiplier: int,
-) {
     i = 0
 
     while i < 10 {
-		sleep_time = i * multiplier;
+        sleep(i * multiplier)
-
+        write_line(i.to_string())
-		thread.sleep(sleep_time)
-		io.write_line(i as str)
 
         i += 1
     }
 }
 
 async {
-	count_slowly(200) # Finishes last
+    count_slowly(200) // Finishes last
-	count_slowly(100) # Finishes second
+    count_slowly(100) // Finishes second
-	count_slowly(50)  # Finishes first
+    count_slowly(50)  // Finishes first
 }
 ```
 
 ### Automatic Memory Management
 
-Dust uses a garbage collector to automatically manage memory. During the analysis phase, Dust will
+Dust uses a garbage collector to automatically manage memory. During the analysiys phase, Dust
-determine the number of references to each value. During execution, the intepreter will check the
+will determine when a value is no longer needed. It can then be removed from memory at runtime.
-context after each statement and remove values that will not be used again.
 
-```dust
+```rust
-x = 0 # x is assigned but never used
+x = 0 // x is assigned but never used
-      # x is removed from memory
+      // x is removed from memory
 
-y = 41 # y is assigned
+y = 41 // y is assigned
-y + 1  # y is kept alive for this statement
+y + 1  // y is kept alive for this statement
-       # y is removed from memory
+       // y is removed from memory
 ```
 
 ### Type Safety
@@ -62,19 +89,19 @@ Dust is statically typed and null-free, but the type of a value can usually be i
 usage. Dust will refuse to run programs with type errors, but will usually not require type
 annotations.
 
-```dust
+```rust
-# These two statements are identical to Dust
+// These two statements are identical to Dust
 x = 1
 x: int = 1
 
-# Numbers with decimals are floats
+// Numbers with decimals are floats
 y = 10.0
 y: float = 10.0
 
-# Strings are enclosed in single or double quotes and are guaranteed to be valid UTF-8
+// Strings are enclosed in single or double quotes and are guaranteed to be valid UTF-8
 z = "Hello, world!"
 z: string = "Hello, world!"
 ```
 
-Aside from the ubiqutous `bool`, `int`, `float`, and `string` types, Dust also has `list`, `map`,
+Aside from the ubiqutous `bool`, `int`, `float`, and `string` types, Dust also has list, maps,
-`range`, structures, enums and functions.
+ranges, structures, enums and functions.

dust-lang/src/parser.rs

@@ -1183,11 +1183,6 @@ mod tests {
     #[test]
     fn tuple_struct_access() {
         let input = "Foo(42, 'bar').0";
-        let mut tree = AbstractSyntaxTree::new();
-
-        if parse_into(input, &mut tree).is_err() {
-            println!("{:?}", tree);
-        }
 
         assert_eq!(
             parse(input),