Add example; Clean up pratt parser

Cargo.lock

@@ -367,6 +367,7 @@ dependencies = [
  "colored",
  "dust-lang",
  "env_logger",
+ "log",
  "nu-ansi-term",
  "reedline",
 ]

dust-lang/src/context.rs

@@ -36,7 +36,7 @@ impl Context {
 
         for (identifier, (value_data, usage_data)) in other.variables.read()?.iter() {
             if let ValueData::Type(Type::Function { .. }) = value_data {
-                log::trace!("Inheriting type of variable {identifier}.");
+                log::trace!("Context inheriting type of {identifier}.");
 
                 self_data.insert(identifier.clone(), (value_data.clone(), usage_data.clone()));
             }
@@ -49,7 +49,7 @@ impl Context {
         let mut self_data = self.variables.write()?;
 
         for (identifier, (value_data, usage_data)) in other.variables.read()?.iter() {
-            log::trace!("Inheriting variable {identifier}.");
+            log::trace!("Context inheriting variable {identifier}.");
 
             self_data.insert(identifier.clone(), (value_data.clone(), usage_data.clone()));
         }
@@ -65,7 +65,7 @@ impl Context {
 
     pub fn get_type(&self, identifier: &Identifier) -> Result<Option<Type>, ValidationError> {
         if let Some((value_data, _)) = self.variables.read()?.get(identifier) {
-            log::trace!("Using {identifier}'s type.");
+            log::trace!("Getting {identifier}'s type.");
 
             let r#type = match value_data {
                 ValueData::Type(r#type) => r#type.clone(),
@@ -105,6 +105,19 @@ impl Context {
         }
     }
 
+    pub fn get_data(
+        &self,
+        identifier: &Identifier,
+    ) -> Result<Option<(ValueData, UsageData)>, RwLockPoisonError> {
+        if let Some(full_data) = self.variables.read()?.get(identifier) {
+            log::trace!("Getting {identifier}'s value.");
+
+            Ok(Some(full_data.clone()))
+        } else {
+            Ok(None)
+        }
+    }
+
     pub fn set_type(&self, identifier: Identifier, r#type: Type) -> Result<(), RwLockPoisonError> {
         log::debug!("Setting {identifier} to type {}.", r#type);
 

dust-lang/src/lib.rs

@@ -88,6 +88,8 @@ impl Interpreter {
             ),
         ];
 
+        log::info!("Start loading standard library...");
+
         let error = std_sources
             .into_par_iter()
             .find_map_any(|(source_id, source)| {
@@ -139,6 +141,8 @@ impl Interpreter {
                     .err()
             });
 
+        log::info!("Finish loading standard library.");
+
         if let Some(error) = error {
             Err(error)
         } else {

dust-lang/src/parser.rs

@@ -12,6 +12,10 @@ use crate::{
 pub type ParserInput<'src> =
     SpannedInput<Token<'src>, SimpleSpan, &'src [(Token<'src>, SimpleSpan)]>;
 
+pub type ParserExtra<'src> = extra::Err<Rich<'src, Token<'src>, SimpleSpan>>;
+
+pub type Comment = String;
+
 pub fn parse<'src>(tokens: &'src [(Token<'src>, SimpleSpan)]) -> Result<AbstractTree, Vec<Error>> {
     let statements = parser(false)
         .parse(tokens.spanned((tokens.len()..tokens.len()).into()))
@@ -28,8 +32,7 @@ pub fn parse<'src>(tokens: &'src [(Token<'src>, SimpleSpan)]) -> Result<Abstract
 
 pub fn parser<'src>(
     allow_built_ins: bool,
-) -> impl Parser<'src, ParserInput<'src>, Vec<Statement>, extra::Err<Rich<'src, Token<'src>, SimpleSpan>>>
-{
+) -> impl Parser<'src, ParserInput<'src>, Vec<Statement>, ParserExtra<'src>> {
     let identifiers: RefCell<HashMap<&str, Identifier>> = RefCell::new(HashMap::new());
     let _custom_types: Rc<RefCell<HashMap<Identifier, Type>>> =
         Rc::new(RefCell::new(HashMap::new()));
@@ -335,8 +338,20 @@ pub fn parser<'src>(
                 )
             });
 
+            let list_index = choice((list.clone(), identifier_expression.clone()))
+                .then(expression.clone().delimited_by(
+                    just(Token::Control(Control::SquareOpen)),
+                    just(Token::Control(Control::SquareClose)),
+                ))
+                .map_with(|(left, right), state| {
+                    Expression::ListIndex(
+                        Box::new(ListIndex::new(left, right)).with_position(state.span()),
+                    )
+                });
+
             let atom = choice((
                 map_index.clone(),
+                list_index.clone(),
                 range.clone(),
                 parsed_function.clone(),
                 list.clone(),
@@ -358,18 +373,6 @@ pub fn parser<'src>(
                         Expression::Logic(Box::new(Logic::Not(expression)).with_position(span))
                     },
                 ),
-                postfix(
-                    2,
-                    expression.clone().delimited_by(
-                        just(Token::Control(Control::SquareOpen)),
-                        just(Token::Control(Control::SquareClose)),
-                    ),
-                    |left, right, span| {
-                        Expression::ListIndex(
-                            Box::new(ListIndex::new(left, right)).with_position(span),
-                        )
-                    },
-                ),
                 postfix(
                     3,
                     turbofish.clone().or_not().then(
@@ -499,6 +502,7 @@ pub fn parser<'src>(
 
             choice((
                 logic_math_indexes_and_function_calls,
+                list_index,
                 map_index,
                 built_in_function_call,
                 range,

dust-shell/Cargo.toml

@@ -14,5 +14,6 @@ clap = { version = "4.5.3", features = ["derive"] }
 colored = "2.1.0"
 dust-lang = { path = "../dust-lang" }
 env_logger = "0.11.3"
+log = "0.4.21"
 nu-ansi-term = "0.50.0"
 reedline = { version = "0.30.0", features = ["sqlite", "system_clipboard"] }

dust-shell/src/main.rs

@@ -5,6 +5,7 @@ use ariadne::sources;
 use clap::Parser;
 use cli::run_shell;
 use colored::Colorize;
+use log::Level;
 
 use std::{
     fs::read_to_string,
@@ -33,10 +34,16 @@ fn main() {
     env_logger::Builder::from_env("DUST_LOG")
         .format(|buffer, record| {
             let args = record.args();
-            let log_level = record.level().to_string().bold();
+            let log_level = match record.level() {
+                Level::Trace => "TRACE".cyan().bold(),
+                Level::Warn => "WARN".yellow().bold(),
+                Level::Debug => "DEBUG".green().bold(),
+                Level::Error => "ERROR".red().bold(),
+                Level::Info => "INFO".white().bold(),
+            };
             let timestamp = buffer.timestamp_seconds().to_string().dimmed();
 
-            writeln!(buffer, "[{log_level} {timestamp}] {args}")
+            writeln!(buffer, "[{} {}] {}", log_level, timestamp, args)
         })
         .init();
 

examples/json_length.ds

@@ -0,0 +1,9 @@
+/*
+	This is is simple program to get the length of a json array.
+
+	Use `cargo run --package dust-shell examples/json_length.ds`
+*/
+input = fs.read_file('examples/assets/data.json')
+data = json.parse(input)
+
+list.length(data)