Add soft/hard returns

examples/easiest.rs

@@ -1,6 +1,6 @@
 use reid::compile;
 
-pub static EASIEST: &str = include_str!("./reid/easy.reid");
+pub static EASIEST: &str = include_str!("./reid/easiest.reid");
 
 fn main() {
     let text = match compile(EASIEST) {

examples/reid/easiest.reid

@@ -7,8 +7,9 @@ fn somethingelse() {
 }
 
 fn main() {
-    let hello = 32 + 2 + 4;
-    let beep = 
-        hello + 100 + somethingelse();
+    let hello = 32 + {
+        2 + somethingelse()
+    };
+    let beep = hello + 5;
     return beep;
 }

src/ast.rs

@@ -201,19 +201,42 @@ impl Parse for FunctionSignature {
     }
 }
 
+#[derive(Debug, Clone, Copy)]
+pub enum ReturnType {
+    Soft,
+    Hard,
+}
+
 #[derive(Debug, Clone)]
-pub struct Block(pub Vec<BlockLevelStatement>, pub Option<Expression>);
+pub struct Block(
+    pub Vec<BlockLevelStatement>,
+    pub Option<(ReturnType, Expression)>,
+);
 
 impl Parse for Block {
     fn parse(mut stream: TokenStream) -> Result<Self, Error> {
         let mut statements = Vec::new();
         let mut return_stmt = None;
         stream.expect(Token::BraceOpen)?;
+
         while !matches!(stream.peek(), Some(Token::BraceClose)) {
+            if let Some((r_type, e)) = return_stmt.take() {
+                println!("Oh no, does this statement lack ;");
+                dbg!(r_type, e);
+            }
             let statement = stream.parse()?;
-            if let BlockLevelStatement::Return(e) = &statement {
-                return_stmt = Some(e.clone());
+            if let BlockLevelStatement::Return((r_type, e)) = &statement {
+                match r_type {
+                    ReturnType::Hard => {
+                        return_stmt = Some((*r_type, e.clone()));
                         break; // Return has to be the last statement
+                               // TODO: Make a mechanism that "can" parse even after this
+                    }
+                    ReturnType::Soft => {
+                        return_stmt = Some((*r_type, e.clone()));
+                        continue; // In theory possible to have lines after a soft return
+                    }
+                };
             }
             statements.push(statement);
         }
@@ -227,7 +250,7 @@ pub enum BlockLevelStatement {
     Let(LetStatement),
     Import(ImportStatement),
     Expression(Expression),
-    Return(Expression),
+    Return((ReturnType, Expression)),
 }
 
 impl Parse for BlockLevelStatement {
@@ -240,12 +263,15 @@ impl Parse for BlockLevelStatement {
                 stream.next();
                 let exp = stream.parse()?;
                 stream.expect(Token::Semi)?;
-                Stmt::Return(exp)
+                Stmt::Return((ReturnType::Hard, exp))
             }
             _ => {
                 if let Ok(e) = stream.parse() {
-                    stream.expect(Token::Semi)?;
+                    if stream.expect(Token::Semi).is_ok() {
                         Stmt::Expression(e)
+                    } else {
+                        Stmt::Return((ReturnType::Soft, e))
+                    }
                 } else {
                     Err(stream.expected_err("expression")?)?
                 }

src/codegen.rs

@@ -2,8 +2,8 @@ use std::collections::{hash_map, HashMap};
 
 use crate::{
     ast::{
-        BinaryOperator, BlockLevelStatement, Expression, FunctionCallExpression,
-        FunctionDefinition, FunctionSignature, TopLevelStatement,
+        BinaryOperator, Block, BlockLevelStatement, Expression, FunctionCallExpression,
+        FunctionDefinition, FunctionSignature, ReturnType, TopLevelStatement,
     },
     llvm_ir::{self, IRBlock, IRFunction, IRModule, IRValue, IRValueType},
 };
@@ -15,8 +15,11 @@ pub struct ScopeData {
 }
 
 impl ScopeData {
-    pub fn inner<'a>(&'a mut self, block: IRBlock<'a>) -> Scope {
-        Scope { block, data: self }
+    pub fn inner<'a, 'b>(&self, block: &'b mut IRBlock<'a>) -> Scope<'a, 'b> {
+        Scope {
+            block,
+            data: self.clone(),
+        }
     }
 
     pub fn var(&self, name: &String) -> Option<&IRValue> {
@@ -55,8 +58,17 @@ impl ScopeData {
 }
 
 pub struct Scope<'a, 'b> {
-    pub block: IRBlock<'a>,
-    pub data: &'b mut ScopeData,
+    pub block: &'b mut IRBlock<'a>,
+    pub data: ScopeData,
+}
+
+impl<'a, 'b> Scope<'a, 'b> {
+    pub fn inner<'c>(&'c mut self) -> Scope<'a, 'c> {
+        Scope {
+            block: self.block,
+            data: self.data.clone(),
+        }
+    }
 }
 
 pub fn codegen_from_statements(statements: Vec<TopLevelStatement>) -> Result<IRModule, Error> {
@@ -89,19 +101,16 @@ impl TopLevelStatement {
         match self {
             TopLevelStatement::FunctionDefinition(FunctionDefinition(sig, block)) => {
                 if let Some((_, ir)) = root_data.function(&sig.name) {
-                    if let Some(ir) = ir.take() {
-                        let mut scope = root_data.inner(module.create_block());
+                    if let Some(ir_function) = ir.take() {
+                        let mut ir_block = module.create_block();
+                        let mut scope = root_data.inner(&mut ir_block);
 
-                        for statement in &block.0 {
-                            statement.codegen(&mut scope)?;
-                        }
-
-                        let value = if let Some(exp) = &block.1 {
-                            exp.codegen(&mut scope)?
-                        } else {
-                            panic!("Void-return type function not yet implemented!");
+                        let (_, value) = match block.codegen(&mut scope)? {
+                            Some(v) => v,
+                            None => panic!("Void-return type function not yet implemented!"),
                         };
-                        ir.add_definition(value, scope.block);
+
+                        ir_function.add_definition(value, ir_block);
                     } else {
                         Err(Error::FunctionAlreadyDefined(sig.name.clone()))?
                     }
@@ -115,6 +124,22 @@ impl TopLevelStatement {
     }
 }
 
+impl Block {
+    pub fn codegen(&self, scope: &mut Scope) -> Result<Option<(ReturnType, IRValue)>, Error> {
+        for statement in &self.0 {
+            statement.codegen(scope)?;
+        }
+
+        let value = if let Some((rt, exp)) = &self.1 {
+            Some((*rt, exp.codegen(scope)?))
+        } else {
+            None
+        };
+
+        Ok(value)
+    }
+}
+
 impl BlockLevelStatement {
     pub fn codegen(&self, scope: &mut Scope) -> Result<(), Error> {
         match self {
@@ -146,7 +171,19 @@ impl Expression {
                     Ok(scope.block.mul(lhs, rhs)?)
                 }
             },
-            BlockExpr(_) => panic!("(BlockExpr) Not implemented!"),
+            BlockExpr(block) => {
+                let mut inner = scope.inner();
+
+                Ok(match block.codegen(&mut inner)? {
+                    Some((r_type, value)) => match r_type {
+                        ReturnType::Soft => value,
+                        ReturnType::Hard => {
+                            panic!("Hard returns in inner blocks not supported yet")
+                        }
+                    },
+                    None => panic!("Void-return type block not yet implemented!"),
+                })
+            }
             FunctionCall(fc) => {
                 let FunctionCallExpression(name, _) = &**fc;
                 if let Some((sig, _)) = scope.data.function(name) {

src/lib.rs

@@ -1,5 +1,5 @@
 use crate::{
-    ast::TopLevelStatement, codegen::codegen_from_statements, lexer::Token, llvm_ir::IRModule,
+    ast::TopLevelStatement, codegen::codegen_from_statements, lexer::Token,
     token_stream::TokenStream,
 };
 

src/llvm_ir.rs

@@ -15,6 +15,19 @@ macro_rules! cstr {
 #[must_use = "value contains raw pointer and must be inserted somewhere"]
 pub struct IRValue(IRValueType, LLVMValueRef);
 
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub enum IRValueType {
+    I32,
+}
+
+impl IRValueType {
+    unsafe fn get_llvm_type(&self, module: &mut IRModule) -> LLVMTypeRef {
+        match *self {
+            Self::I32 => LLVMInt32TypeInContext(module.context),
+        }
+    }
+}
+
 fn into_cstring<T: Into<String>>(value: T) -> CString {
     let string = value.into();
     unsafe { CString::from_vec_with_nul_unchecked((string + "\0").into_bytes()) }
@@ -83,19 +96,6 @@ impl Drop for IRModule {
     }
 }
 
-#[derive(Clone, Debug, PartialEq, Eq)]
-pub enum IRValueType {
-    I32,
-}
-
-impl IRValueType {
-    unsafe fn get_llvm_type(&self, codegen: &mut IRModule) -> LLVMTypeRef {
-        match *self {
-            Self::I32 => LLVMInt32TypeInContext(codegen.context),
-        }
-    }
-}
-
 #[derive(Clone, Debug)]
 pub struct IRFunction {
     value: IRValue,