checkpoint

src/backend/eval.rs

@@ -159,7 +159,7 @@ impl Backend<ObjectModule> {
             .arg(executable_path)
             .output()?;
 
-        if !output.stderr.is_empty() {
+        if !output.status.success() {
             return Err(EvalError::Linker(
                 std::string::String::from_utf8_lossy(&output.stderr).to_string(),
             ));

src/backend/into_crane.rs

@@ -413,7 +413,10 @@ impl<M: Module> Backend<M> {
                     // negative number for us. Which sets the high bits, which makes Cranelift unhappy.
                     // So first we cast the i8 as u8, to get rid of the whole concept of sign extension,
                     // and *then* we cast to i64.
-                    Ok((builder.ins().iconst(types::I8, v as u8 as i64), ConstantType::I8))
+                    Ok((
+                        builder.ins().iconst(types::I8, v as u8 as i64),
+                        ConstantType::I8,
+                    ))
                 }
                 Value::I16(_, v) => Ok((
                     // see above note for the "... as ... as"

src/eval/primtype.rs

@@ -113,6 +113,7 @@ impl FromStr for PrimitiveType {
             "u16" => Ok(PrimitiveType::U16),
             "u32" => Ok(PrimitiveType::U32),
             "u64" => Ok(PrimitiveType::U64),
+            "void" => Ok(PrimitiveType::Void),
             _ => Err(UnknownPrimType::UnknownPrimType(s.to_owned())),
         }
     }
@@ -190,6 +191,8 @@ impl PrimitiveType {
             (PrimitiveType::I64, Value::I32(x)) => Ok(Value::I64(*x as i64)),
             (PrimitiveType::I64, Value::I64(x)) => Ok(Value::I64(*x)),
 
+            (PrimitiveType::Void, Value::Void) => Ok(Value::Void),
+
             _ => Err(PrimOpError::UnsafeCast {
                 from: PrimitiveType::try_from(source)?,
                 to: *self,

src/ir/ast.rs

@@ -228,9 +228,13 @@ where
                 .text("print")
                 .append(allocator.space())
                 .append(allocator.text(var.as_ref().to_string())),
-            Expression::Bind(_, var, _, expr) => allocator
+            Expression::Bind(_, var, ty, expr) => allocator
                 .text(var.as_ref().to_string())
                 .append(allocator.space())
+                .append(allocator.text(":"))
+                .append(allocator.space())
+                .append(ty.pretty(allocator))
+                .append(allocator.space())
                 .append(allocator.text("="))
                 .append(allocator.space())
                 .append(expr.pretty(allocator)),

src/syntax/ast.rs

@@ -124,6 +124,7 @@ pub enum Expression {
     Reference(Location, String),
     Cast(Location, String, Box<Expression>),
     Primitive(Location, String, Vec<Expression>),
+    Block(Location, Vec<Statement>),
 }
 
 impl PartialEq for Expression {
@@ -145,6 +146,10 @@ impl PartialEq for Expression {
                 Expression::Primitive(_, prim2, args2) => prim1 == prim2 && args1 == args2,
                 _ => false,
             },
+            Expression::Block(_, stmts1) => match other {
+                Expression::Block(_, stmts2) => stmts1 == stmts2,
+                _ => false,
+            },
         }
     }
 }

src/syntax/eval.rs

@@ -35,25 +35,7 @@ impl Program {
                     }
                 }
 
-                TopLevel::Statement(Statement::Binding(_, name, value)) => {
+                TopLevel::Statement(stmt) => last_result = stmt.eval(&mut stdout, &mut env)?,
-                    let actual_value = value.eval(&env)?;
-                    env.insert(name.clone().intern(), actual_value);
-                    last_result = Value::Void;
-                }
-
-                TopLevel::Statement(Statement::Print(loc, name)) => {
-                    let value = env
-                        .get(&name.clone().intern())
-                        .ok_or_else(|| EvalError::LookupFailed(loc.clone(), name.name.clone()))?;
-                    let value = if let Value::Number(x) = value {
-                        Value::U64(*x)
-                    } else {
-                        value.clone()
-                    };
-                    let line = format!("{} = {}\n", name, value);
-                    stdout.push_str(&line);
-                    last_result = Value::Void;
-                }
             }
         }
 
@@ -61,10 +43,41 @@ impl Program {
     }
 }
 
+impl Statement {
+    fn eval(
+        &self,
+        stdout: &mut String,
+        env: &mut ScopedMap<ArcIntern<String>, Value<Expression>>,
+    ) -> Result<Value<Expression>, EvalError<Expression>> {
+        match self {
+            Statement::Binding(_, name, value) => {
+                let actual_value = value.eval(stdout, env)?;
+                env.insert(name.clone().intern(), actual_value);
+                Ok(Value::Void)
+            }
+
+            Statement::Print(loc, name) => {
+                let value = env
+                    .get(&name.clone().intern())
+                    .ok_or_else(|| EvalError::LookupFailed(loc.clone(), name.name.clone()))?;
+                let value = if let Value::Number(x) = value {
+                    Value::U64(*x)
+                } else {
+                    value.clone()
+                };
+                let line = format!("{} = {}\n", name, value);
+                stdout.push_str(&line);
+                Ok(Value::Void)
+            }
+        }
+    }
+}
+
 impl Expression {
     fn eval(
         &self,
-        env: &ScopedMap<ArcIntern<String>, Value<Expression>>,
+        stdout: &mut String,
+        env: &mut ScopedMap<ArcIntern<String>, Value<Expression>>,
     ) -> Result<Value<Expression>, EvalError<Expression>> {
         match self {
             Expression::Value(_, v) => match v {
@@ -90,7 +103,7 @@ impl Expression {
 
             Expression::Cast(_, target, expr) => {
                 let target_type = PrimitiveType::from_str(target)?;
-                let value = expr.eval(env)?;
+                let value = expr.eval(stdout, env)?;
                 Ok(target_type.safe_cast(&value)?)
             }
 
@@ -99,11 +112,21 @@ impl Expression {
 
                 for arg in args.iter() {
                     // yay, recursion! makes this pretty straightforward
-                    arg_values.push(arg.eval(env)?);
+                    arg_values.push(arg.eval(stdout, env)?);
                 }
 
                 Ok(Value::calculate(op, arg_values)?)
             }
+
+            Expression::Block(_, stmts) => {
+                let mut result = Value::Void;
+
+                for stmt in stmts.iter() {
+                    result = stmt.eval(stdout, env)?;
+                }
+
+                Ok(result)
+            }
         }
     }
 }

src/syntax/parser.lalrpop

@@ -87,11 +87,13 @@ OptionalName: Option<Name> = {
 }
 
 Arguments: Vec<Name> = {
-    <mut args:Arguments> <arg:Argument> => {
+    <mut args:Arguments> "," <arg:Argument> => {
         args.push(arg);
         args
     },
 
+    <arg:Argument> => vec![arg],
+
     => Vec::new(),
 }
 
@@ -214,7 +216,7 @@ AtomicExpression: Expression = {
     // just a number
     <l: @L> <n:"<num>"> <end: @L> => Expression::Value(Location::new(file_idx, l..end), Value::Number(n.0, n.1, n.2)),
     // this expression could actually be a block!
-    "{" <stmts:Statements> "}" => unimplemented!(),
+    <s:@L> "{" <stmts:Statements> "}" <e:@L> => Expression::Block(Location::new(file_idx, s..e), stmts),
     // finally, let people parenthesize expressions and get back to a
     // lower precedence
     "(" <e:Expression> ")" => e,

src/syntax/pretty.rs

@@ -105,6 +105,25 @@ where
                 let comma_sepped_args = allocator.intersperse(args, CommaSep {});
                 call.append(comma_sepped_args.parens())
             }
+            Expression::Block(_, stmts) => match stmts.split_last() {
+                None => allocator.text("()"),
+                Some((last, &[])) => last.pretty(allocator),
+                Some((last, start)) => {
+                    let mut result = allocator.text("{").append(allocator.hardline());
+
+                    for stmt in start.iter() {
+                        result = result
+                            .append(stmt.pretty(allocator))
+                            .append(allocator.text(";"))
+                            .append(allocator.hardline());
+                    }
+
+                    result
+                        .append(last.pretty(allocator))
+                        .append(allocator.hardline())
+                        .append(allocator.text("}"))
+                }
+            },
         }
     }
 }

src/syntax/validate.rs

@@ -180,7 +180,10 @@ impl Statement {
 }
 
 impl Expression {
-    fn validate(&self, variable_map: &ScopedMap<String, Location>) -> (Vec<Error>, Vec<Warning>) {
+    fn validate(
+        &self,
+        variable_map: &mut ScopedMap<String, Location>,
+    ) -> (Vec<Error>, Vec<Warning>) {
         match self {
             Expression::Value(_, _) => (vec![], vec![]),
             Expression::Reference(_, var) if variable_map.contains_key(var) => (vec![], vec![]),
@@ -207,6 +210,19 @@ impl Expression {
                     warnings.append(&mut warn);
                 }
 
+                (errors, warnings)
+            }
+            Expression::Block(_, stmts) => {
+                let mut errors = vec![];
+                let mut warnings = vec![];
+
+                for stmt in stmts.iter() {
+                    let (mut local_errors, mut local_warnings) = stmt.validate(variable_map);
+
+                    errors.append(&mut local_errors);
+                    warnings.append(&mut local_warnings);
+                }
+
                 (errors, warnings)
             }
         }

src/type_infer/convert.rs

@@ -71,9 +71,10 @@ pub fn convert_top_level(
                 args.iter().map(|x| ArcIntern::new(x.to_string())).collect();
             assert_eq!(argtypes.len(), iargs.len());
             let mut function_args = vec![];
-            for (arg_name, arg_type) in iargs.iter().zip(argtypes) {
+            for ((arg_name, arg_type), orig_name) in iargs.iter().zip(argtypes).zip(args) {
                 bindings.insert(arg_name.clone(), arg_type.clone());
-                function_args.push((arg_name.clone(), arg_type));
+                function_args.push((arg_name.clone(), arg_type.clone()));
+                constraint_db.push(Constraint::IsSomething(orig_name.location, arg_type));
             }
 
             let (expr, ty) = convert_expression(expr, constraint_db, renames, bindings);
@@ -150,7 +151,7 @@ fn convert_statement(
 fn convert_expression(
     expression: syntax::Expression,
     constraint_db: &mut Vec<Constraint>,
-    renames: &ScopedMap<ArcIntern<String>, ArcIntern<String>>,
+    renames: &mut ScopedMap<ArcIntern<String>, ArcIntern<String>>,
     bindings: &mut ScopedMap<ArcIntern<String>, ir::TypeOrVar>,
 ) -> (ir::Expression<ir::TypeOrVar>, ir::TypeOrVar) {
     match expression {
@@ -282,6 +283,23 @@ fn convert_expression(
                 )
             }
         }
+
+        syntax::Expression::Block(loc, stmts) => {
+            let mut ret_type = ir::TypeOrVar::Primitive(PrimitiveType::Void);
+            let mut exprs = vec![];
+
+            for statement in stmts {
+                let expr = convert_statement(statement, constraint_db, renames, bindings);
+
+                ret_type = expr.type_of();
+                exprs.push(expr);
+            }
+
+            (
+                ir::Expression::Block(loc, ret_type.clone(), exprs),
+                ret_type,
+            )
+        }
     }
 }
 

src/type_infer/finalize.rs

@@ -6,6 +6,26 @@ pub fn finalize_program(
     mut program: Program<TypeOrVar>,
     resolutions: &TypeResolutions,
 ) -> Program<Type> {
+    println!("RESOLUTIONS:");
+    for (name, ty) in resolutions.iter() {
+        println!("{} => {}", name, ty);
+    }
+    println!("PROGRAM:");
+    {
+        use pretty::{DocAllocator, Pretty};
+        let allocator = pretty::BoxAllocator;
+        allocator
+            .text("---------------")
+            .append(allocator.hardline())
+            .append(program.pretty(&allocator))
+            .1
+            .render_colored(
+                70,
+                pretty::termcolor::StandardStream::stdout(pretty::termcolor::ColorChoice::Auto),
+            )
+            .expect("rendering works");
+    }
+
     Program {
         items: program
             .items

src/type_infer/solve.rs

@@ -25,6 +25,8 @@ pub enum Constraint {
     ConstantNumericType(Location, TypeOrVar),
     /// The two types should be equivalent
     Equivalent(Location, TypeOrVar, TypeOrVar),
+    /// The given type can be resolved to something
+    IsSomething(Location, TypeOrVar),
 }
 
 impl fmt::Display for Constraint {
@@ -43,6 +45,7 @@ impl fmt::Display for Constraint {
             Constraint::NumericType(_, ty) => write!(f, "NUMERIC {}", ty),
             Constraint::ConstantNumericType(_, ty) => write!(f, "CONST_NUMERIC {}", ty),
             Constraint::Equivalent(_, ty, ty2) => write!(f, "EQUIVALENT {} => {}", ty, ty2),
+            Constraint::IsSomething(_, ty) => write!(f, "SOMETHING {}", ty),
         }
     }
 }
@@ -213,6 +216,10 @@ impl From<TypeInferenceError> for Diagnostic<usize> {
                     prim
                 ))
             }
+            TypeInferenceError::CouldNotSolve(Constraint::IsSomething(loc, _)) => {
+                loc.labelled_error("could not infer type")
+                    .with_message("Could not find *any* type information; is this an unused function argument?")
+            }
         }
     }
 }
@@ -253,6 +260,11 @@ pub fn solve_constraints(
     let mut resolutions = HashMap::new();
     let mut changed_something = true;
 
+    println!("CONSTRAINTS:");
+    for constraint in constraint_db.iter() {
+        println!("{}", constraint);
+    }
+
     // We want to run this inference endlessly, until either we have solved all of our
     // constraints. Internal to the loop, we have a check that will make sure that we
     // do (eventually) stop.
@@ -275,6 +287,16 @@ pub fn solve_constraints(
                 // Currently, all of our types are printable
                 Constraint::Printable(_loc, _ty) => changed_something = true,
 
+                // If we're looking for a type to be something (anything!), and it's not a type
+                // variable, then yay, we've solved it.
+                Constraint::IsSomething(_, TypeOrVar::Function(_, _))
+                | Constraint::IsSomething(_, TypeOrVar::Primitive(_)) => changed_something = true,
+
+                // Otherwise, we'll keep looking for it.
+                Constraint::IsSomething(_, TypeOrVar::Variable(_, _)) => {
+                    constraint_db.push(constraint);
+                }
+
                 // Case #1a: We have two primitive types. If they're equal, we've discharged this
                 // constraint! We can just continue. If they're not equal, add an error and then
                 // see what else we come up with.