parser: pass through token ranges in errors & add simple diagnostics output that cites the source file

Cargo.toml

@@ -7,4 +7,5 @@ edition = "2021"
 laddertypes = { path = "../lib-laddertypes" }
 tisc = { path = "../lib-tisc" }
 iterate-text = "0.0.1"
+tiny-ansi = "0.1.0"
 

src/lexer.rs

@@ -79,11 +79,19 @@ where
     }
 }
 
-
+#[derive(Clone, Copy, PartialEq, Debug)]
-#[derive(Clone, Debug)]
 pub struct InputRegionTag {
-    begin: usize,
+    pub begin: usize,
-    end: usize
+    pub end: usize
+}
+
+impl Default for InputRegionTag {
+    fn default() -> Self {
+        InputRegionTag {
+            begin: 0,
+            end: 0
+        }
+    }
 }
 
 impl InputRegionTag {
@@ -271,9 +279,8 @@ where
 
                 LexerState::TypeTerm(s) => {
                     if *c == '=' || *c == '↦' || *c == ';' {
-                        if let Some(token) = state.clone().into_token() {
+                        let token = state.clone().into_token().unwrap();
                         return Some((region, Ok(token)));
-                        }
                     } else {
                         if let Some(c) = self.chars.next() {
                             self.position += 1;

src/main.rs

@@ -2,6 +2,7 @@ use {
     std::collections::HashMap,
     std::sync::{Arc, RwLock},
     std::{boxed::Box, ops::Deref},
+    tiny_ansi::TinyAnsi
 };
 
 mod expr;
@@ -12,36 +13,71 @@ mod runtime;
 mod symbols;
 
 use crate::{
+    lexer::InputRegionTag,
     expr::{LTExpr, Statement},
     procedure_compiler::ProcedureCompiler,
     symbols::Scope,
 };
 
-fn compile(
+fn print_diagnostic(
-    scope: &Arc<RwLock<Scope>>,
+    path: &str,
-    name: &str,
+    region: InputRegionTag,
-    source: impl Iterator<Item = char>,
+    message: String
-) -> Vec<tisc::assembler::AssemblyWord> {
+) {
-    ProcedureCompiler::new(scope)
+    let lines = iterate_text::file::lines::IterateFileLines::new(path);
-        .compile(
+
-            &parser::parse_expr(
+    let mut line_region = InputRegionTag::default();
-                &scope.read().unwrap().typectx,
+
-                &mut lexer::LTIRLexer::from(source.peekable())
+    let n_before = 3;
-                    .filter(|tok| match tok {
+    let n_after  = 3;
-                        (_, Ok(lexer::LTIRToken::Comment(_))) => false,
+
-                        _ => true
+    let mut last_lines = Vec::new();
-                    })
+    let mut next_lines = 0;
-                    .peekable(),
+
-            )
+    println!("\n{}:", path.green());
-            .expect("syntax error"),
+    for (i, l) in lines.enumerate() {
-        )
+        line_region.end += l.chars().count();
-        .into_asm(&name.into())
+
+        last_lines.push((i+1, l.clone()));
+        if last_lines.len() > n_before {
+            last_lines.remove(0);
         }
 
+        if region.begin >= line_region.begin &&
+            region.begin < line_region.end {
+
+            next_lines = n_after;
+
+            let column_begin = region.begin - line_region.begin;
+            let column_end   = region.end   - line_region.begin;
+
+            // display the source line
+            for (j,ll) in last_lines.iter() {
+                print!("{}\t{}{}",
+                    format!("{}",j).to_string().bright_white(),
+                    "|".yellow().bold(),
+                    ll.white());
+            }
+
+            print!("\t{}", "|".yellow().bold());
+            for _ in 0..column_begin { print!("{}", ".".magenta().bold()); }
+            for _ in column_begin..column_end { print!("{}", "^".magenta().bold()); }
+            print!("\n");
+
+            print!("{} [{}-{}]: {}\n", "error".bright_red(), column_begin, column_end, message);
+        }
+        else if next_lines > 0 {
+            next_lines -= 1;
+            print!("{}:\t{}{}", format!("{}", i+1).to_string().bright_white(), "|".yellow().bold(), l.white());
+        }
+
+        line_region.begin = line_region.end;
+    }
+}
 
 /* TODO:
- *   - Parser error reporting
  *   - Compiler error reporting
+ *   - parse float literals
  *   - write to address resulting from expression
  *   - sized objects
  *   - Typecheck for LTExpr::Application
@@ -57,19 +93,39 @@ fn main() {
     let main_scope = Scope::with_parent(&root_scope);
     let typectx = main_scope.read().unwrap().typectx.clone();
 
+    /* open source file
+     */
     let args: Vec<String> = std::env::args().collect();
     let path = &args[1];
     let iter_chars = iterate_text::file::characters::IterateFileCharacters::new(path);
 
+    /* compile source file
+     */
+    let mut lexer = lexer::LTIRLexer::from( iter_chars.peekable() );
+    let mut program_tokens = lexer.filter(|tok| match tok {
+                        (_, Ok(lexer::LTIRToken::Comment(_))) => false,
+                        _ => true
+                    })
+                    .peekable();
+
+    match parser::parse_expr( &typectx, &mut program_tokens ) {
+        Ok( ast ) => {
+            let bytecode = ProcedureCompiler::new(&main_scope)
+                .compile( &ast )
+                .into_asm(&"main".into());
+
+            eprintln!("{}", "Compiled successfully.\n======================\n".green());
+
             /* link assembly-program to symbols
              */
-    linker.add_procedure("main", compile(&main_scope, "main", iter_chars));
+            linker.add_procedure("main", bytecode);
 
             /* load & run compiled bytecode
              */
             let main_addr = linker
                 .get_link_addr(&"main".into())
                 .expect("'main' not linked");
+        
             vm.load(linker.link_total().expect("could not link"));
             vm.execute(main_addr);
 
@@ -78,3 +134,14 @@ fn main() {
                 vm.data_stack
             );
         }
+        Err( (region, parse_error) ) => {
+            print_diagnostic(
+                path,
+                region,
+                format!("{:?}", parse_error)
+            );
+
+            eprintln!("=======\nerror: Parse Error\n");
+        }
+    }
+}

src/parser.rs

@@ -21,7 +21,7 @@ pub enum ParseError {
 pub fn parse_expect<It>(
     tokens: &mut Peekable<It>,
     expected_token: LTIRToken,
-) -> Result<(), ParseError>
+) -> Result<(), (InputRegionTag, ParseError)>
 where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 {
     match tokens.next() {
@@ -29,24 +29,24 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
             if t == expected_token {
                 Ok(())
             } else {
-                Err(ParseError::UnexpectedToken)
+                Err((region, ParseError::UnexpectedToken))
             }
         }
-        Some((region, Err(err))) => Err(ParseError::LexError(err)),
+        Some((region, Err(err))) => Err((region, ParseError::LexError(err))),
-        None => Err(ParseError::UnexpectedEnd),
+        None => Err((InputRegionTag::default(), ParseError::UnexpectedEnd)),
     }
 }
 
 /* parse symbol name
  */
-pub fn parse_symbol<It>(tokens: &mut Peekable<It>) -> Result<String, ParseError>
+pub fn parse_symbol<It>(tokens: &mut Peekable<It>) -> Result<String, (InputRegionTag, ParseError)>
 where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 {
     match tokens.next() {
         Some((region, Ok(LTIRToken::Symbol(name)))) => Ok(name),
-        Some((region, Ok(_))) => Err(ParseError::UnexpectedToken),
+        Some((region, Ok(_))) => Err((region, ParseError::UnexpectedToken)),
-        Some((region, Err(err))) => Err(ParseError::LexError(err)),
+        Some((region, Err(err))) => Err((region, ParseError::LexError(err))),
-        None => Err(ParseError::UnexpectedEnd),
+        None => Err((InputRegionTag::default(), ParseError::UnexpectedEnd)),
     }
 }
 
@@ -56,16 +56,17 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 pub fn parse_type_tag<It>(
     typectx: &Arc<RwLock<laddertypes::dict::TypeDict>>,
     tokens: &mut Peekable<It>,
-) -> Result<Option<laddertypes::TypeTerm>, ParseError>
+) -> Result<Option<laddertypes::TypeTerm>, (InputRegionTag, ParseError)>
 where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 {
-    if let Some((region, peektok)) = tokens.peek().clone() {
+    let peek = { tokens.peek().cloned() };
-        match peektok.clone() {
+    if let Some((region, peektok)) = peek {
+        match peektok {
             Ok(LTIRToken::AssignType(typeterm_str)) => {
                 tokens.next();
                 match typectx.write().unwrap().parse(typeterm_str.as_str()) {
                     Ok(typeterm) => Ok(Some(typeterm)),
-                    Err(parse_error) => Err(ParseError::TypeParseError(parse_error)),
+                    Err(parse_error) => Err((region, ParseError::TypeParseError(parse_error))),
                 }
             }
             _ => Ok(None),
@@ -109,7 +110,7 @@ impl VariableBinding {
 pub fn parse_binding_expr<It>(
     typectx: &Arc<RwLock<laddertypes::dict::TypeDict>>,
     tokens: &mut Peekable<It>,
-) -> Result< VariableBinding, ParseError>
+) -> Result< VariableBinding, (InputRegionTag, ParseError)>
 where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 {
     if let Some((region, peektok)) = tokens.peek().clone() {
@@ -126,11 +127,11 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
                     typtag: parse_type_tag(typectx, tokens)?
                 })
             }
-            Err(err) => Err(ParseError::LexError(err.clone())),
+            Err(err) => Err((*region, ParseError::LexError(err.clone()))),
-            _ => Err(ParseError::UnexpectedToken)
+            _ => Err((*region, ParseError::UnexpectedToken))
         }
     } else {
-        Err(ParseError::UnexpectedEnd)
+        Err((InputRegionTag::default(), ParseError::UnexpectedEnd))
     }
 }
 
@@ -140,13 +141,16 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 pub fn parse_binding_block<It>(
     typectx: &Arc<RwLock<laddertypes::dict::TypeDict>>,
     tokens: &mut Peekable<It>,
-) -> Result< Vec<VariableBinding>, ParseError>
+) -> Result< Vec<VariableBinding>, (InputRegionTag, ParseError)>
 where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 {
+    let mut last_region = InputRegionTag::default();
+
     let _ = parse_expect(tokens, LTIRToken::BlockOpen)?;
 
     let mut bindings = Vec::new();
     while let Some((region, peektok)) = tokens.peek() {
+        last_region = *region;
         match peektok {
             Ok(LTIRToken::BlockClose) => {
                 tokens.next();
@@ -159,18 +163,18 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
                 bindings.push(parse_binding_expr(typectx, tokens)?);
             }
             Err(err) => {
-                return Err(ParseError::LexError(err.clone()));
+                return Err((last_region, ParseError::LexError(err.clone())));
             }
         }
     }
 
-    Err(ParseError::UnexpectedEnd)
+    Err((last_region, ParseError::UnexpectedEnd))
 }
 
 pub fn parse_statement<It>(
     typectx: &Arc<RwLock<laddertypes::dict::TypeDict>>,
     tokens: &mut Peekable<It>,
-) -> Result<crate::expr::Statement, ParseError>
+) -> Result<crate::expr::Statement, (InputRegionTag, ParseError)>
 where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 {
     if let Some((region, peektok)) = tokens.peek() {
@@ -237,17 +241,17 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
                 let _ = parse_expect(tokens, LTIRToken::StatementSep)?;
                 Ok(Statement::Expr(expr))
             }
-            Err(err) => Err(ParseError::LexError(err.clone())),
+            Err(err) => Err((*region, ParseError::LexError(err.clone()))),
         }
     } else {
-        Err(ParseError::UnexpectedEnd)
+        Err((InputRegionTag::default(), ParseError::UnexpectedEnd))
     }
 }
 
 pub fn parse_statement_block<It>(
     typectx: &Arc<RwLock<laddertypes::dict::TypeDict>>,
     tokens: &mut Peekable<It>,
-) -> Result<Vec<Statement>, ParseError>
+) -> Result<Vec<Statement>, (InputRegionTag, ParseError)>
 where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 {
     let _ = parse_expect(tokens, LTIRToken::BlockOpen)?;
@@ -263,33 +267,33 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
                 statements.push(parse_statement(typectx, tokens)?);
             }
             Err(err) => {
-                return Err(ParseError::LexError(err.clone()));
+                return Err((*region, ParseError::LexError(err.clone())));
             }
         }
     }
 
-    Err(ParseError::UnexpectedEnd)
+    Err((InputRegionTag::default(), ParseError::UnexpectedEnd))
 }
 
 pub fn parse_atom<It>(
     tokens: &mut Peekable<It>,
-) -> Result<crate::expr::LTExpr, ParseError>
+) -> Result<crate::expr::LTExpr, (InputRegionTag, ParseError)>
 where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 {
     match tokens.next() {
         Some((region, Ok(LTIRToken::Symbol(sym)))) => Ok(LTExpr::symbol(sym.as_str())),
         Some((region, Ok(LTIRToken::Char(c)))) => Ok(LTExpr::lit_uint(c as u64)),
         Some((region, Ok(LTIRToken::Num(n)))) => Ok(LTExpr::lit_uint(n as u64)),
-        Some((region, Ok(_))) => Err(ParseError::UnexpectedToken),
+        Some((region, Ok(_))) => Err((region, ParseError::UnexpectedToken)),
-        Some((region, Err(err))) => Err(ParseError::LexError(err)),
+        Some((region, Err(err))) => Err((region, ParseError::LexError(err))),
-        None => Err(ParseError::UnexpectedEnd),
+        None => Err((InputRegionTag::default(), ParseError::UnexpectedEnd)),
     }
 }
 
 pub fn parse_expr<It>(
     typectx: &Arc<RwLock<laddertypes::dict::TypeDict>>,
     tokens: &mut Peekable<It>,
-) -> Result<crate::expr::LTExpr, ParseError>
+) -> Result<crate::expr::LTExpr, (InputRegionTag, ParseError)>
 where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
 {
     let mut children = Vec::new();
@@ -309,7 +313,7 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
                         body: Box::new(body),
                     });
                 } else {
-                    return Err(ParseError::UnexpectedToken);
+                    return Err((*region, ParseError::UnexpectedToken));
                 }
             }
             Ok(LTIRToken::ExprOpen) => {
@@ -369,7 +373,7 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
                 children.push(parse_atom(tokens)?);
             }
             Err(err) => {
-                return Err(ParseError::LexError(err.clone()));
+                return Err((*region, ParseError::LexError(err.clone())));
             }
         }
     }
@@ -382,7 +386,7 @@ where It: Iterator<Item = (InputRegionTag, Result<LTIRToken, LexError>)>
             body: children,
         })
     } else {
-        Err(ParseError::UnexpectedEnd)
+        Err((InputRegionTag::default(), ParseError::UnexpectedEnd))
     }
 }