Process Struct ASTs into MIR

README.md

@@ -38,6 +38,7 @@ Currently missing relevant features (TODOs) are:
 - ~~Extern functions~~ (DONE)
 - ~~Strings~~ (DONE)
 - Loops
+- Debug Information
 
 ### Why "Reid"
 

libtest.sh

@@ -14,7 +14,7 @@
 
 BINARY="$(echo $1 | cut -d'.' -f1)"".out"
 
-make clean SRC=$1 && make SRC=$1 && echo ""
+make clean SRC=$1 ; make SRC=$1 && echo ""
 
 $BINARY ; echo "Return value: ""$?"
 

reid-llvm-lib/src/builder.rs

@@ -5,12 +5,15 @@ use std::{cell::RefCell, rc::Rc};
 
 use crate::{
     BlockData, ConstValue, FunctionData, Instr, InstructionData, ModuleData, TerminatorKind, Type,
-    util::match_types,
+    TypeData, util::match_types,
 };
 
 #[derive(Clone, Hash, Copy, PartialEq, Eq)]
 pub struct ModuleValue(pub(crate) usize);
 
+#[derive(Clone, Hash, Copy, PartialEq, Eq)]
+pub struct TypeValue(pub(crate) ModuleValue, pub(crate) usize);
+
 #[derive(Clone, Hash, Copy, PartialEq, Eq)]
 pub struct FunctionValue(pub(crate) ModuleValue, pub(crate) usize);
 
@@ -25,6 +28,13 @@ pub struct ModuleHolder {
     pub(crate) value: ModuleValue,
     pub(crate) data: ModuleData,
     pub(crate) functions: Vec<FunctionHolder>,
+    pub(crate) types: Vec<TypeHolder>,
+}
+
+#[derive(Clone)]
+pub struct TypeHolder {
+    pub(crate) value: TypeValue,
+    pub(crate) data: TypeData,
 }
 
 #[derive(Clone)]
@@ -65,6 +75,7 @@ impl Builder {
             value,
             data,
             functions: Vec::new(),
+            types: Vec::new(),
         });
         value
     }

reid-llvm-lib/src/compile.rs

@@ -196,6 +196,10 @@ impl ModuleHolder {
                 context.context_ref,
             );
 
+            for _ty in &self.types {
+                todo!("Do something with types!");
+            }
+
             // Compile the contents
 
             let mut functions = HashMap::new();

reid-llvm-lib/src/lib.rs

@@ -263,3 +263,14 @@ pub enum TerminatorKind {
     Br(BlockValue),
     CondBr(InstructionValue, BlockValue, BlockValue),
 }
+
+#[derive(Debug, PartialEq, Eq, Clone, Hash)]
+pub struct TypeData {
+    name: String,
+    kind: CustomTypeKind,
+}
+
+#[derive(Debug, PartialEq, Eq, Clone, Hash)]
+pub enum CustomTypeKind {
+    Struct(Vec<Type>),
+}

reid/examples/cli.rs

@@ -1,4 +1,4 @@
-use std::{env, fs, path::PathBuf};
+use std::{env, error::Error, fs, path::PathBuf};
 
 use reid::compile;
 use reid_lib::compile::CompileOutput;

reid/examples/testcodegen.rs

@@ -163,6 +163,7 @@ fn main() {
             name: "test module".to_owned(),
             imports: vec![],
             functions: vec![fibonacci, main],
+            typedefs: Vec::new(),
             path: None,
             is_main: true,
         }],

reid/src/ast/mod.rs

@@ -26,6 +26,7 @@ pub enum TypeKind {
     U128,
     String,
     Array(Box<TypeKind>, u64),
+    Custom(String),
 }
 
 #[derive(Debug, Clone)]
@@ -43,11 +44,13 @@ pub enum ExpressionKind {
     VariableName(String),
     Literal(Literal),
     Array(Vec<Expression>),
-    Index(Box<Expression>, u64),
+    ArrayIndex(Box<Expression>, u64),
+    StructIndex(Box<Expression>, String),
     Binop(BinaryOperator, Box<Expression>, Box<Expression>),
     FunctionCall(Box<FunctionCallExpression>),
     BlockExpr(Box<Block>),
     IfExpr(Box<IfExpression>),
+    StructExpression(StructExpression),
 }
 
 #[derive(Debug, Clone, Copy)]
@@ -129,6 +132,12 @@ pub enum ReturnType {
     Hard,
 }
 
+#[derive(Debug, Clone)]
+pub struct StructExpression {
+    name: String,
+    fields: Vec<(String, Expression)>,
+}
+
 #[derive(Debug, Clone)]
 pub struct Block(
     pub Vec<BlockLevelStatement>,
@@ -142,7 +151,8 @@ pub struct VariableReference(pub VariableReferenceKind, pub TokenRange);
 #[derive(Debug, Clone)]
 pub enum VariableReferenceKind {
     Name(String, TokenRange),
-    Index(Box<VariableReference>, u64),
+    ArrayIndex(Box<VariableReference>, u64),
+    StructIndex(Box<VariableReference>, String),
 }
 
 #[derive(Debug, Clone)]
@@ -157,11 +167,31 @@ pub enum BlockLevelStatement {
     Return(ReturnType, Expression),
 }
 
+#[derive(Debug)]
+pub struct TypeDefinition {
+    name: String,
+    kind: TypeDefinitionKind,
+    range: TokenRange,
+}
+
+#[derive(Debug)]
+pub enum TypeDefinitionKind {
+    Struct(Vec<StructDefinitionField>),
+}
+
+#[derive(Debug)]
+pub struct StructDefinitionField {
+    name: String,
+    ty: Type,
+    range: TokenRange,
+}
+
 #[derive(Debug)]
 pub enum TopLevelStatement {
     Import(ImportStatement),
     ExternFunction(FunctionSignature),
     FunctionDefinition(FunctionDefinition),
+    TypeDefinition(TypeDefinition),
 }
 
 #[derive(Debug)]

reid/src/ast/parse.rs

@@ -76,10 +76,24 @@ impl Parse for PrimaryExpression {
             )
         } else if let Ok(ifexpr) = stream.parse() {
             Expression(Kind::IfExpr(Box::new(ifexpr)), stream.get_range().unwrap())
+        } else if let (Some(Token::Identifier(_)), Some(Token::BraceOpen)) =
+            (stream.peek(), stream.peek2())
+        {
+            Expression(
+                Kind::StructExpression(stream.parse()?),
+                stream.get_range().unwrap(),
+            )
         } else if let Some(token) = stream.next() {
             match &token {
                 Token::Identifier(v) => {
-                    Expression(Kind::VariableName(v.clone()), stream.get_range().unwrap())
+                    if let Some(Token::BraceOpen) = stream.peek() {
+                        Expression(
+                            Kind::StructExpression(stream.parse()?),
+                            stream.get_range().unwrap(),
+                        )
+                    } else {
+                        Expression(Kind::VariableName(v.clone()), stream.get_range().unwrap())
+                    }
                 }
                 Token::DecimalValue(v) => Expression(
                     Kind::Literal(Literal::Number(*v)),
@@ -120,11 +134,21 @@ impl Parse for PrimaryExpression {
             Err(stream.expected_err("expression")?)?
         };
 
-        while let Ok(ValueIndex(idx)) = stream.parse() {
-            expr = Expression(
-                ExpressionKind::Index(Box::new(expr), idx),
-                stream.get_range().unwrap(),
-            );
+        while let Ok(index) = stream.parse::<ValueIndex>() {
+            match index {
+                ValueIndex::Array(ArrayValueIndex(idx)) => {
+                    expr = Expression(
+                        ExpressionKind::ArrayIndex(Box::new(expr), idx),
+                        stream.get_range().unwrap(),
+                    );
+                }
+                ValueIndex::Struct(StructValueIndex(name)) => {
+                    expr = Expression(
+                        ExpressionKind::StructIndex(Box::new(expr), name),
+                        stream.get_range().unwrap(),
+                    );
+                }
+            }
         }
 
         Ok(PrimaryExpression(expr))
@@ -401,9 +425,9 @@ impl Parse for VariableReference {
                 stream.get_range().unwrap(),
             );
 
-            while let Ok(ValueIndex(idx)) = stream.parse() {
+            while let Ok(ArrayValueIndex(idx)) = stream.parse() {
                 var_ref = VariableReference(
-                    VariableReferenceKind::Index(Box::new(var_ref), idx),
+                    VariableReferenceKind::ArrayIndex(Box::new(var_ref), idx),
                     stream.get_range().unwrap(),
                 );
             }
@@ -415,21 +439,101 @@ impl Parse for VariableReference {
     }
 }
 
-#[derive(Debug, Clone, Copy)]
-pub struct ValueIndex(u64);
+impl Parse for StructExpression {
+    fn parse(mut stream: TokenStream) -> Result<Self, Error> {
+        let Some(Token::Identifier(name)) = stream.next() else {
+            return Err(stream.expected_err("struct identifier")?);
+        };
+        stream.expect(Token::BraceOpen)?;
+        let named_list = stream.parse::<NamedFieldList<Expression>>()?;
+        let fields = named_list.0.into_iter().map(|f| (f.0, f.1)).collect();
+
+        stream.expect(Token::BraceClose)?;
+
+        Ok(StructExpression { name, fields })
+    }
+}
+
+#[derive(Debug)]
+pub struct NamedFieldList<T: Parse + std::fmt::Debug>(Vec<NamedField<T>>);
+
+impl<T: Parse + std::fmt::Debug> Parse for NamedFieldList<T> {
+    fn parse(mut stream: TokenStream) -> Result<Self, Error> {
+        let mut fields = Vec::new();
+        while let Ok(field) = stream.parse() {
+            fields.push(field);
+            match stream.peek() {
+                Some(Token::Comma) => {
+                    stream.next();
+                } // Consume comma
+                Some(Token::BraceClose) => break,
+                Some(_) | None => Err(stream.expected_err("another field or closing brace")?)?,
+            }
+        }
+        Ok(NamedFieldList(fields))
+    }
+}
+
+#[derive(Debug)]
+pub struct NamedField<T: Parse + std::fmt::Debug>(String, T, TokenRange);
+
+impl<T: Parse + std::fmt::Debug> Parse for NamedField<T> {
+    fn parse(mut stream: TokenStream) -> Result<Self, Error> {
+        let Some(Token::Identifier(field_name)) = stream.next() else {
+            return Err(stream.expected_err("type name")?);
+        };
+        stream.expect(Token::Colon)?;
+        let value = stream.parse()?;
+
+        Ok(NamedField(field_name, value, stream.get_range().unwrap()))
+    }
+}
+
+#[derive(Debug, Clone)]
+pub enum ValueIndex {
+    Array(ArrayValueIndex),
+    Struct(StructValueIndex),
+}
 
 impl Parse for ValueIndex {
+    fn parse(mut stream: TokenStream) -> Result<Self, Error> {
+        match stream.peek() {
+            Some(Token::BracketOpen) => Ok(ValueIndex::Array(stream.parse()?)),
+            Some(Token::Dot) => Ok(ValueIndex::Struct(stream.parse()?)),
+            _ => Err(stream.expected_err("value or struct index")?),
+        }
+    }
+}
+
+#[derive(Debug, Clone, Copy)]
+pub struct ArrayValueIndex(u64);
+
+impl Parse for ArrayValueIndex {
     fn parse(mut stream: TokenStream) -> Result<Self, Error> {
         stream.expect(Token::BracketOpen)?;
         if let Some(Token::DecimalValue(idx)) = stream.next() {
             stream.expect(Token::BracketClose)?;
-            Ok(ValueIndex(idx))
+            Ok(ArrayValueIndex(idx))
         } else {
             return Err(stream.expected_err("array index (number)")?);
         }
     }
 }
 
+#[derive(Debug, Clone)]
+pub struct StructValueIndex(String);
+
+impl Parse for StructValueIndex {
+    fn parse(mut stream: TokenStream) -> Result<Self, Error> {
+        stream.expect(Token::Dot)?;
+        if let Some(Token::Identifier(name)) = stream.next() {
+            Ok(StructValueIndex(name))
+        } else {
+            return Err(stream.expected_err("struct index (number)")?);
+        }
+    }
+}
+
 impl Parse for BlockLevelStatement {
     fn parse(mut stream: TokenStream) -> Result<Self, Error> {
         use BlockLevelStatement as Stmt;
@@ -476,6 +580,33 @@ impl Parse for SetStatement {
     }
 }
 
+#[derive(Debug)]
+pub struct StructDefinition(String, Vec<StructDefinitionField>, TokenRange);
+
+impl Parse for StructDefinition {
+    fn parse(mut stream: TokenStream) -> Result<Self, Error> {
+        stream.expect(Token::Struct)?;
+
+        let Some(Token::Identifier(name)) = stream.next() else {
+            return Err(stream.expected_err("identifier")?);
+        };
+
+        stream.expect(Token::BraceOpen)?;
+        let named_fields = stream.parse::<NamedFieldList<Type>>()?;
+        let fields = named_fields
+            .0
+            .into_iter()
+            .map(|f| StructDefinitionField {
+                name: f.0,
+                ty: f.1,
+                range: f.2,
+            })
+            .collect();
+        stream.expect(Token::BraceClose)?;
+        Ok(StructDefinition(name, fields, stream.get_range().unwrap()))
+    }
+}
+
 impl Parse for TopLevelStatement {
     fn parse(mut stream: TokenStream) -> Result<Self, Error> {
         use TopLevelStatement as Stmt;
@@ -491,6 +622,14 @@ impl Parse for TopLevelStatement {
             Some(Token::FnKeyword) | Some(Token::PubKeyword) => {
                 Stmt::FunctionDefinition(stream.parse()?)
             }
+            Some(Token::Struct) => {
+                let StructDefinition(name, fields, range) = stream.parse::<StructDefinition>()?;
+                Stmt::TypeDefinition(TypeDefinition {
+                    name,
+                    kind: TypeDefinitionKind::Struct(fields),
+                    range,
+                })
+            }
             _ => Err(stream.expected_err("import or fn")?)?,
         })
     }

reid/src/ast/process.rs

@@ -15,6 +15,7 @@ impl ast::Module {
     pub fn process(&self) -> mir::Module {
         let mut imports = Vec::new();
         let mut functions = Vec::new();
+        let mut typedefs = Vec::new();
 
         use ast::TopLevelStatement::*;
         for stmt in &self.top_level_statements {
@@ -62,6 +63,23 @@ impl ast::Module {
                     };
                     functions.push(def);
                 }
+                TypeDefinition(ast::TypeDefinition { name, kind, range }) => {
+                    let def = mir::TypeDefinition {
+                        name: name.clone(),
+                        kind: match kind {
+                            ast::TypeDefinitionKind::Struct(struct_definition_fields) => {
+                                mir::TypeDefinitionKind::Struct(
+                                    struct_definition_fields
+                                        .iter()
+                                        .map(|s| (s.name.clone(), s.ty.clone().into()))
+                                        .collect(),
+                                )
+                            }
+                        },
+                        meta: (*range).into(),
+                    };
+                    typedefs.push(def);
+                }
             }
         }
 
@@ -71,6 +89,7 @@ impl ast::Module {
             functions,
             path: self.path.clone(),
             is_main: self.is_main,
+            typedefs,
         }
     }
 }
@@ -151,8 +170,14 @@ impl ast::VariableReferenceKind {
                     (*range).into(),
                 ))
             }
-            ast::VariableReferenceKind::Index(var_ref, idx) => {
-                mir::IndexedVariableReferenceKind::Index(Box::new(var_ref.process()), *idx)
+            ast::VariableReferenceKind::ArrayIndex(var_ref, idx) => {
+                mir::IndexedVariableReferenceKind::ArrayIndex(Box::new(var_ref.process()), *idx)
+            }
+            ast::VariableReferenceKind::StructIndex(var_ref, name) => {
+                mir::IndexedVariableReferenceKind::StructIndex(
+                    Box::new(var_ref.process()),
+                    name.clone(),
+                )
             }
         }
     }
@@ -193,11 +218,24 @@ impl ast::Expression {
             ast::ExpressionKind::Array(expressions) => {
                 mir::ExprKind::Array(expressions.iter().map(|e| e.process()).collect())
             }
-            ast::ExpressionKind::Index(expression, idx) => mir::ExprKind::Index(
+            ast::ExpressionKind::ArrayIndex(expression, idx) => mir::ExprKind::ArrayIndex(
                 Box::new(expression.process()),
                 mir::TypeKind::Vague(mir::VagueType::Unknown),
                 *idx,
             ),
+            ast::ExpressionKind::StructExpression(struct_init) => mir::ExprKind::Struct(
+                struct_init.name.clone(),
+                struct_init
+                    .fields
+                    .iter()
+                    .map(|(n, e)| (n.clone(), e.process()))
+                    .collect(),
+            ),
+            ast::ExpressionKind::StructIndex(expression, name) => mir::ExprKind::StructIndex(
+                Box::new(expression.process()),
+                mir::TypeKind::Vague(mir::VagueType::Unknown),
+                name.clone(),
+            ),
         };
 
         mir::Expression(kind, self.1.into())
@@ -249,6 +287,7 @@ impl From<ast::TypeKind> for mir::TypeKind {
                 mir::TypeKind::Array(Box::new(mir::TypeKind::from(*type_kind.clone())), *length)
             }
             ast::TypeKind::String => mir::TypeKind::StringPtr,
+            ast::TypeKind::Custom(_) => todo!("Add processing for custom types"),
         }
     }
 }

reid/src/codegen.rs

@@ -173,7 +173,7 @@ impl IndexedVariableReference {
                 .get(name)
                 .cloned()
                 .map(|v| (v, Vec::new())),
-            mir::IndexedVariableReferenceKind::Index(inner, idx) => {
+            mir::IndexedVariableReferenceKind::ArrayIndex(inner, idx) => {
                 let (inner_val, mut indices) = inner.get_stack_value(scope)?;
 
                 match &inner_val.1 {
@@ -184,6 +184,9 @@ impl IndexedVariableReference {
                     _ => panic!("Tried to codegen indexing a non-indexable value!"),
                 }
             }
+            mir::IndexedVariableReferenceKind::StructIndex(indexed_variable_reference, _) => {
+                todo!("codegen for indexed var refrence")
+            }
         }
     }
 }
@@ -385,7 +388,7 @@ impl mir::Expression {
                     None
                 }
             }
-            mir::ExprKind::Index(expression, val_t, idx) => {
+            mir::ExprKind::ArrayIndex(expression, val_t, idx) => {
                 let array = expression.codegen(scope)?;
                 let ptr = scope
                     .block
@@ -428,6 +431,10 @@ impl mir::Expression {
 
                 Some(array)
             }
+            mir::ExprKind::StructIndex(expression, type_kind, _) => {
+                todo!("codegen for struct index")
+            }
+            mir::ExprKind::Struct(_, items) => todo!("codegen for struct expression"),
         }
     }
 }
@@ -511,6 +518,7 @@ impl TypeKind {
             TypeKind::Array(elem_t, _) => Type::Ptr(Box::new(elem_t.get_type())),
             TypeKind::Void => Type::Void,
             TypeKind::Vague(_) => panic!("Tried to compile a vague type!"),
+            TypeKind::CustomType(_, custom_type_kind) => todo!("codegen for custom type"),
         }
     }
 }

reid/src/lexer.rs

@@ -36,6 +36,8 @@ pub enum Token {
     False,
     /// `extern`
     Extern,
+    /// `struct`
+    Struct,
 
     // Symbols
     /// `;`
@@ -74,6 +76,8 @@ pub enum Token {
     BracketClose,
     /// `,`
     Comma,
+    /// `.`
+    Dot,
 
     Eof,
 }
@@ -211,6 +215,7 @@ pub fn tokenize<T: Into<String>>(to_tokenize: T) -> Result<Vec<FullToken>, Error
                     "false" => Token::False,
                     "extern" => Token::Extern,
                     "pub" => Token::PubKeyword,
+                    "struct" => Token::Struct,
                     _ => Token::Identifier(value),
                 };
                 variant
@@ -249,6 +254,7 @@ pub fn tokenize<T: Into<String>>(to_tokenize: T) -> Result<Vec<FullToken>, Error
             '{' => Token::BraceOpen,
             '}' => Token::BraceClose,
             ',' => Token::Comma,
+            '.' => Token::Dot,
             // Invalid token
             _ => Err(Error::InvalidToken(*character, cursor.position))?,
         };

reid/src/mir/display.rs

@@ -23,6 +23,9 @@ impl Display for Module {
         for import in &self.imports {
             writeln!(inner_f, "{}", import)?;
         }
+        for typedef in &self.typedefs {
+            writeln!(inner_f, "{}", typedef)?;
+        }
         for fun in &self.functions {
             writeln!(inner_f, "{}", fun)?;
         }
@@ -36,6 +39,31 @@ impl Display for Import {
     }
 }
 
+impl Display for TypeDefinition {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, "type {} = ", self.name)?;
+        Display::fmt(&self.kind, f)
+    }
+}
+
+impl Display for TypeDefinitionKind {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            TypeDefinitionKind::Struct(items) => {
+                write!(f, "struct ")?;
+                f.write_char('{')?;
+                writeln!(f)?;
+                let mut state = Default::default();
+                let mut inner_f = PadAdapter::wrap(f, &mut state);
+                for (field_name, field_ty) in items {
+                    writeln!(inner_f, "{}: {:?},", field_name, field_ty)?;
+                }
+                f.write_char('}')
+            }
+        }
+    }
+}
+
 impl Display for FunctionDefinition {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         write!(
@@ -130,7 +158,7 @@ impl Display for ExprKind {
             ExprKind::FunctionCall(fc) => Display::fmt(fc, f),
             ExprKind::If(if_exp) => Display::fmt(&if_exp, f),
             ExprKind::Block(block) => Display::fmt(block, f),
-            ExprKind::Index(expression, elem_ty, idx) => {
+            ExprKind::ArrayIndex(expression, elem_ty, idx) => {
                 Display::fmt(&expression, f)?;
                 write!(f, "<{}>", elem_ty)?;
                 write_index(f, *idx)
@@ -152,6 +180,28 @@ impl Display for ExprKind {
                 }
                 f.write_char(']')
             }
+            ExprKind::Struct(name, items) => {
+                write!(f, "{} ", name)?;
+
+                f.write_char('{')?;
+                let mut state = Default::default();
+                let mut inner_f = PadAdapter::wrap(f, &mut state);
+                let mut iter = items.iter();
+                if let Some((name, expr)) = iter.next() {
+                    write!(inner_f, "\n{}: {}", name, expr)?;
+                    while let Some((name, expr)) = iter.next() {
+                        writeln!(inner_f, ",")?;
+                        write!(inner_f, "{}: {}", name, expr)?;
+                    }
+                    writeln!(inner_f, "")?;
+                }
+                f.write_char('}')
+            }
+            ExprKind::StructIndex(expression, type_kind, name) => {
+                Display::fmt(&expression, f)?;
+                write!(f, "<{}>", type_kind)?;
+                write_access(f, name)
+            }
         }
     }
 }
@@ -190,10 +240,14 @@ impl Display for IndexedVariableReference {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match &self.kind {
             IndexedVariableReferenceKind::Named(name) => Display::fmt(name, f),
-            IndexedVariableReferenceKind::Index(variable_reference_kind, idx) => {
-                Display::fmt(&variable_reference_kind, f)?;
+            IndexedVariableReferenceKind::ArrayIndex(var_ref, idx) => {
+                Display::fmt(&var_ref, f)?;
                 write_index(f, *idx)
             }
+            IndexedVariableReferenceKind::StructIndex(var_ref, name) => {
+                Display::fmt(&var_ref, f)?;
+                write_access(f, name)
+            }
         }
     }
 }
@@ -254,3 +308,8 @@ fn write_index(f: &mut std::fmt::Formatter<'_>, idx: u64) -> std::fmt::Result {
     Display::fmt(&idx, f)?;
     f.write_char(']')
 }
+
+fn write_access(f: &mut std::fmt::Formatter<'_>, name: &String) -> std::fmt::Result {
+    f.write_char('.')?;
+    Display::fmt(name, f)
+}

reid/src/mir/mod.rs

@@ -4,7 +4,7 @@
 
 use std::path::PathBuf;
 
-use crate::token_stream::TokenRange;
+use crate::{ast::Type, token_stream::TokenRange};
 
 mod display;
 pub mod linker;
@@ -65,6 +65,8 @@ pub enum TypeKind {
     StringPtr,
     #[error("[{0}; {1}]")]
     Array(Box<TypeKind>, u64),
+    #[error("{0} ({1})")]
+    CustomType(String, CustomTypeKind),
     #[error(transparent)]
     Vague(#[from] VagueType),
 }
@@ -79,6 +81,14 @@ pub enum VagueType {
     TypeRef(usize),
 }
 
+#[derive(Debug, Clone, PartialEq, Eq, thiserror::Error)]
+pub enum CustomTypeKind {
+    #[error("struct({0:?})")]
+    Struct(Vec<TypeKind>),
+    #[error("CustomType")]
+    Unknown,
+}
+
 impl TypeKind {
     pub fn known(&self) -> Result<TypeKind, VagueType> {
         if let TypeKind::Vague(vague) = self {
@@ -107,6 +117,7 @@ impl TypeKind {
             TypeKind::U128 => false,
             TypeKind::StringPtr => false,
             TypeKind::Array(_, _) => false,
+            TypeKind::CustomType(_, _) => false,
         }
     }
 
@@ -126,8 +137,9 @@ impl TypeKind {
             Bool => true,
             Vague(_) => false,
             Void => false,
-            TypeKind::StringPtr => false,
+            StringPtr => false,
             Array(_, _) => false,
+            TypeKind::CustomType(_, _) => false,
         }
     }
 }
@@ -217,8 +229,10 @@ pub struct Import(pub Vec<String>, pub Metadata);
 #[derive(Debug)]
 pub enum ExprKind {
     Variable(NamedVariableRef),
-    Index(Box<Expression>, TypeKind, u64),
+    ArrayIndex(Box<Expression>, TypeKind, u64),
+    StructIndex(Box<Expression>, TypeKind, String),
     Array(Vec<Expression>),
+    Struct(String, Vec<(String, Expression)>),
     Literal(Literal),
     BinOp(BinaryOperator, Box<Expression>, Box<Expression>),
     FunctionCall(FunctionCall),
@@ -294,7 +308,8 @@ pub struct IndexedVariableReference {
 #[derive(Debug)]
 pub enum IndexedVariableReferenceKind {
     Named(NamedVariableRef),
-    Index(Box<IndexedVariableReference>, u64),
+    ArrayIndex(Box<IndexedVariableReference>, u64),
+    StructIndex(Box<IndexedVariableReference>, String),
 }
 
 #[derive(Debug)]
@@ -306,11 +321,24 @@ pub enum StmtKind {
     Expression(Expression),
 }
 
+#[derive(Debug)]
+pub struct TypeDefinition {
+    pub name: String,
+    pub kind: TypeDefinitionKind,
+    pub meta: Metadata,
+}
+
+#[derive(Debug)]
+pub enum TypeDefinitionKind {
+    Struct(Vec<(String, Type)>),
+}
+
 #[derive(Debug)]
 pub struct Module {
     pub name: String,
     pub imports: Vec<Import>,
     pub functions: Vec<FunctionDefinition>,
+    pub typedefs: Vec<TypeDefinition>,
     pub path: Option<PathBuf>,
     pub is_main: bool,
 }

reid/src/mir/typecheck.rs

@@ -427,7 +427,7 @@ impl Expression {
                 Ok((_, ty)) => Ok(ty),
                 Err(e) => Err(e),
             },
-            ExprKind::Index(expression, elem_ty, idx) => {
+            ExprKind::ArrayIndex(expression, elem_ty, idx) => {
                 // Try to unwrap hint type from array if possible
                 let hint_t = hint_t.map(|t| match t {
                     TypeKind::Array(type_kind, _) => &type_kind,
@@ -487,6 +487,10 @@ impl Expression {
                     }
                 }
             }
+            ExprKind::StructIndex(expression, type_kind, _) => {
+                todo!("typechecking for struct index")
+            }
+            ExprKind::Struct(_, items) => todo!("typechecking for struct expression"),
         }
     }
 }
@@ -500,7 +504,7 @@ impl IndexedVariableReference {
             IndexedVariableReferenceKind::Named(NamedVariableRef(_, name, _)) => {
                 Ok(storage.get(&name).cloned())
             }
-            IndexedVariableReferenceKind::Index(inner_ref, _) => {
+            IndexedVariableReferenceKind::ArrayIndex(inner_ref, _) => {
                 if let Some(var) = inner_ref.get_variable(storage)? {
                     match &var.ty {
                         TypeKind::Array(inner_ty, _) => Ok(Some(ScopeVariable {
@@ -513,6 +517,9 @@ impl IndexedVariableReference {
                     Ok(None)
                 }
             }
+            IndexedVariableReferenceKind::StructIndex(indexed_variable_reference, _) => {
+                todo!("struct index refrence typecheck")
+            }
         }
     }
 }

reid/src/mir/typeinference.rs

@@ -161,7 +161,7 @@ impl IndexedVariableReference {
             super::IndexedVariableReferenceKind::Named(NamedVariableRef(_, name, _)) => {
                 Ok(hints.find_hint(&name))
             }
-            super::IndexedVariableReferenceKind::Index(inner, _) => {
+            super::IndexedVariableReferenceKind::ArrayIndex(inner, _) => {
                 if let Some((mutable, inner_ref)) = inner.find_hint(hints)? {
                     // Check that the resolved type is at least an array, no
                     // need for further resolution.
@@ -177,6 +177,9 @@ impl IndexedVariableReference {
                     Ok(None)
                 }
             }
+            super::IndexedVariableReferenceKind::StructIndex(indexed_variable_reference, _) => {
+                todo!("struct index refrence type inference")
+            }
         }
     }
 }
@@ -283,7 +286,7 @@ impl Expression {
                     ReturnKind::Soft => Ok(block_ref.1),
                 }
             }
-            ExprKind::Index(expression, index_ty, _) => {
+            ExprKind::ArrayIndex(expression, index_ty, _) => {
                 let expr_ty = expression.infer_types(state, type_refs)?;
 
                 // Check that the resolved type is at least an array, no
@@ -336,6 +339,10 @@ impl Expression {
                     }
                 }
             }
+            ExprKind::StructIndex(expression, type_kind, _) => {
+                todo!("type inference for struct indexes")
+            }
+            ExprKind::Struct(_, items) => todo!("type inference for struct expression"),
         }
     }
 }

reid/src/mir/types.rs

@@ -1,3 +1,5 @@
+use crate::util::try_all;
+
 use super::*;
 
 #[derive(Debug, Clone)]
@@ -87,7 +89,7 @@ impl ReturnType for Expression {
             Block(block) => block.return_type(),
             FunctionCall(fcall) => fcall.return_type(),
             If(expr) => expr.return_type(),
-            Index(expression, _, _) => {
+            ArrayIndex(expression, _, _) => {
                 let expr_type = expression.return_type()?;
                 if let (_, TypeKind::Array(elem_ty, _)) = expr_type {
                     Ok((ReturnKind::Soft, *elem_ty))
@@ -106,6 +108,18 @@ impl ReturnType for Expression {
                     TypeKind::Array(Box::new(first.1), expressions.len() as u64),
                 ))
             }
+            StructIndex(expression, type_kind, _) => todo!("todo return type for struct index"),
+            Struct(name, items) => {
+                let f_types = try_all(items.iter().map(|e| e.1.return_type()).collect())
+                    .map_err(|e| unsafe { e.get_unchecked(0).clone() })?
+                    .iter()
+                    .map(|r| r.1.clone())
+                    .collect();
+                Ok((
+                    ReturnKind::Soft,
+                    TypeKind::CustomType(name.clone(), CustomTypeKind::Struct(f_types)),
+                ))
+            }
         }
     }
 }
@@ -165,9 +179,12 @@ impl IndexedVariableReference {
     pub fn get_name(&self) -> String {
         match &self.kind {
             IndexedVariableReferenceKind::Named(NamedVariableRef(_, name, _)) => name.clone(),
-            IndexedVariableReferenceKind::Index(inner, idx) => {
+            IndexedVariableReferenceKind::ArrayIndex(inner, idx) => {
                 format!("{}[{}]", inner.get_name(), idx)
             }
+            IndexedVariableReferenceKind::StructIndex(inner, name) => {
+                format!("{}.{}", inner.get_name(), name)
+            }
         }
     }
 
@@ -176,7 +193,8 @@ impl IndexedVariableReference {
             IndexedVariableReferenceKind::Named(NamedVariableRef(ty, _, _)) => {
                 *ty = new_ty.clone();
             }
-            IndexedVariableReferenceKind::Index(inner, _) => inner.update_type(new_ty),
+            IndexedVariableReferenceKind::ArrayIndex(inner, _) => inner.update_type(new_ty),
+            IndexedVariableReferenceKind::StructIndex(inner, _) => inner.update_type(new_ty),
         }
     }
 }

reid/src/token_stream.rs

@@ -63,6 +63,14 @@ impl<'a, 'b> TokenStream<'a, 'b> {
         }
     }
 
+    pub fn peek2(&mut self) -> Option<Token> {
+        if self.tokens.len() < (self.position + 1) {
+            None
+        } else {
+            Some(self.tokens[self.position + 1].token.clone())
+        }
+    }
+
     /// Parse the next value of trait Parse. If the parse succeeded, the related
     /// tokens are consumed, otherwise token stream does not advance.
     ///

reid_src/struct.reid

@@ -0,0 +1,15 @@
+// Arithmetic, function calls and imports!
+
+struct Test {
+    field: i32,
+    second: u32
+}
+
+fn main() -> u32 {
+    let value = Test {
+        field: 5,
+        second: 3,
+    };
+
+    return Test.second;
+}