Merge pull request #47 from mist-go/closures-and-bodies

Closures and fix statement bodies

crates/codegen/src/expr.rs

@@ -85,7 +85,7 @@ impl GenRust for Expression {
                 prefixes,
                 postfixes,
             } => {
-                cg.add(&prefixes.get_rust());
+                prefixes.gen_rust(ctx, cg);
                 initial.gen_rust(ctx, cg);
                 cg.add(&Some(prefixes).get_rust());
                 for postfix in postfixes {
@@ -110,23 +110,41 @@ impl GenRust for Expression {
     }
 }
 
-impl GetRust for Prefix {
+impl GenRust for Prefix {
-    fn get_rust(&self) -> String {
+    fn gen_rust(&self, ctx: &mut Context, cg: &mut RustCodegen) {
         match self {
-            Self::Deref => "*",
+            Self::Deref => cg.add("*"),
-            Self::Ref => "&",
+            Self::Ref => cg.add("&"),
-            Self::RefMut => "&mut ",
+            Self::RefMut => cg.add("&mut "),
-            Self::Not => "!",
+            Self::Not => cg.add("!"),
-            Self::New(_) => "",
+            Self::New(_) => cg.add(""),
-            Self::Neg => "-",
+            Self::Neg => cg.add("-"),
+            Self::Closure(ty, args) => {
+                cg.add("|");
+                for (i, arg) in args.iter().enumerate() {
+                    if i > 0 {
+                        cg.add(", ");
+                    }
+
+                    arg.gen_rust(ctx, cg);
+                }
+                cg.add("| ");
+
+                if let Some(ty) = ty {
+                    cg.add("-> ");
+                    cg.add(&ty.get_rust());
+                    cg.add(" ");
+                }
+            }
         }
-        .to_string()
     }
 }
 
-impl GetRust for Vec<Prefix> {
+impl GenRust for Vec<Prefix> {
-    fn get_rust(&self) -> String {
+    fn gen_rust(&self, ctx: &mut Context, cg: &mut RustCodegen) {
-        self.into_iter().map(Prefix::get_rust).collect()
+        for prefix in self {
+            prefix.gen_rust(ctx, cg);
+        }
     }
 }
 

crates/codegen/src/lib.rs

@@ -94,6 +94,17 @@ impl RustCodegen {
             }
         }
     }
+
+    pub fn ensure_brackets_body(&mut self, ctx: &mut Context, body: &StatementBody) {
+        match body {
+            StatementBody::Expression(expr) => self.ensure_brackets_expr(ctx, expr),
+
+            StatementBody::Statement(expr) => {
+                ctx.expr_ensure_semicolon = true;
+                self.ensure_brackets_expr(ctx, expr);
+            }
+        }
+    }
 }
 
 impl GenRust for Attribute {

crates/codegen/src/statement.rs

@@ -26,6 +26,18 @@ impl GenRust for Block {
     }
 }
 
+impl GenRust for StatementBody {
+    fn gen_rust(&self, ctx: &mut Context, cg: &mut RustCodegen) {
+        match self {
+            Self::Expression(expr) => expr.gen_rust(ctx, cg),
+            Self::Statement(stmt) => {
+                ctx.expr_ensure_semicolon = true;
+                stmt.gen_rust(ctx, cg);
+            }
+        }
+    }
+}
+
 impl GenRust for Statement {
     fn gen_rust(&self, ctx: &mut Context, cg: &mut RustCodegen) {
         match self {
@@ -76,18 +88,18 @@ impl GenRust for Statement {
                 cg.add("if ");
                 initial.condition.gen_rust(ctx, cg);
                 cg.add(" ");
-                cg.ensure_brackets_expr(ctx, &initial.body);
+                cg.ensure_brackets_body(ctx, &initial.body);
 
                 for else_if_branch in else_if {
                     cg.add("else if");
                     else_if_branch.condition.gen_rust(ctx, cg);
                     cg.add(" ");
-                    cg.ensure_brackets_expr(ctx, &else_if_branch.body);
+                    cg.ensure_brackets_body(ctx, &else_if_branch.body);
                 }
 
                 if let Some(else_br) = else_branch {
                     cg.add(" else ");
-                    cg.ensure_brackets_expr(ctx, else_br);
+                    cg.ensure_brackets_body(ctx, else_br);
                 }
             }
 
@@ -95,12 +107,12 @@ impl GenRust for Statement {
                 cg.add("while ");
                 condition.gen_rust(ctx, cg);
                 cg.add(" ");
-                cg.ensure_brackets_expr(ctx, body);
+                cg.ensure_brackets_body(ctx, body);
             }
 
             Statement::Loop(body) => {
                 cg.add("loop ");
-                cg.ensure_brackets_expr(ctx, body);
+                cg.ensure_brackets_body(ctx, body);
             }
 
             Statement::CStyleFor {
@@ -156,7 +168,7 @@ impl GenRust for Statement {
                 pattern.gen_rust(ctx, cg);
                 cg.add(" in ");
                 iterator.gen_rust(ctx, cg);
-                cg.ensure_brackets_expr(ctx, body);
+                cg.ensure_brackets_body(ctx, body);
             }
 
             Statement::Return(expr) => {

crates/parser/src/ast/expr.rs

@@ -62,6 +62,7 @@ pub enum Prefix {
     New(Option<Generics>),
     Not,
     Neg,
+    Closure(Option<TypeExpr>, Vec<VarDecl>),
 }
 
 #[derive(Debug, Clone, Serialize)]

crates/parser/src/ast/statement.rs

@@ -8,27 +8,33 @@ pub struct Block(
     pub Option<Spanned<Expression>>,
 );
 
+#[derive(Debug, Clone, Serialize)]
+pub enum StatementBody {
+    Statement(Expression),
+    Expression(Expression),
+}
+
 #[derive(Debug, Clone, Serialize)]
 pub enum Statement {
     Block(Block),
     If {
         initial: StatementBranch,
         else_if: Vec<StatementBranch>,
-        else_branch: Option<Box<Expression>>,
+        else_branch: Option<StatementBody>,
     },
-    Loop(Expression),
+    Loop(StatementBody),
     While(StatementBranch),
     CStyleFor {
         init: Expression,
         condition: Expression,
         update: Expression,
-        body: Expression,
+        body: StatementBody,
     },
     For {
         mutable: bool,
         pattern: Pattern,
         iterator: Expression,
-        body: Box<Expression>,
+        body: StatementBody,
     },
     Match(Expression, Vec<(Vec<Pattern>, Expression)>),
 
@@ -54,28 +60,28 @@ pub struct VarDeclStmt {
 #[derive(Debug, Clone, Serialize)]
 pub struct StatementBranch {
     pub condition: Expression,
-    pub body: Box<Expression>,
+    pub body: Box<StatementBody>,
 }
 
 impl Statement {
     pub fn is_block(&self) -> bool {
         match self {
-            Self::Block(_) => true,
+            Self::Block(_)
-            Self::If {
+            | Self::Match(_, _)
-                initial,
+            | Self::While(_)
-                else_if,
+            | Self::For { .. }
-                else_branch,
+            | Self::Loop(..)
-            } => {
+            | Self::CStyleFor { .. }
-                else_branch
+            | Self::If { .. } => true,
-                    .as_ref()
+            _ => false,
-                    .map(|v| v.is_block())
-                    .unwrap_or_default()
-                    || else_if
-                        .last()
-                        .map(|b| b.body.is_block())
-                        .unwrap_or_default()
-                    || initial.body.is_block()
         }
+    }
+}
+
+impl StatementBody {
+    pub fn is_soft_return(&self) -> bool {
+        match self {
+            Self::Expression(_) => true,
             _ => false,
         }
     }

crates/parser/src/grammar.pest

@@ -91,7 +91,7 @@ generics = { "<" ~ (generic ~ ("," ~ generic)*)? ~ ">" }
 // ======================================================
 
 tuple_type = {
-    "(" ~ (type_expr ~ ("," ~ type_expr)*)? ~ ")"
+    "[" ~ (type_expr ~ ("," ~ type_expr)*)? ~ "]"
 }
 
 path_type = {
@@ -343,6 +343,10 @@ statement = _{
   | (expr ~ semicolon)
 }
 
+statement_wrapper = { statement }
+
+statement_body = { statement_wrapper | expr }
+
 // ------------------------------------------------------
 // BASIC STATEMENTS
 // ------------------------------------------------------
@@ -384,7 +388,7 @@ control_flow = {
   | block
 }
 
-statement_branch = { "(" ~ expr ~ ")" ~ statement }
+statement_branch = { "(" ~ expr ~ ")" ~ statement_body }
 
 else_if = {
     "else" ~ "if" ~ statement_branch
@@ -395,7 +399,7 @@ else_if_list = {
 }
 
 if_stmt = {
-    "if" ~ statement_branch ~ else_if_list ~ ("else" ~ statement)?
+    "if" ~ statement_branch ~ else_if_list ~ ("else" ~ statement_body)?
 }
 
 // ------------------------------------------------------
@@ -407,15 +411,15 @@ while_stmt = {
 }
 
 c_for_stmt = {
-    "for" ~ "(" ~ statement ~ statement ~ expr ~ ")" ~ statement
+    "for" ~ "(" ~ statement ~ statement ~ expr ~ ")" ~ statement_body
 }
 
 for_stmt = {
-    "for" ~ "(" ~ mutable? ~ pattern ~ ":" ~ expr ~ ")" ~ statement
+    "for" ~ "(" ~ mutable? ~ pattern ~ ":" ~ expr ~ ")" ~ statement_body
 }
 
 loop_stmt = {
-    "loop" ~ statement
+    "loop" ~ statement_body
 }
 
 // ------------------------------------------------------
@@ -436,6 +440,12 @@ match_stmt = {
 // EXPRESSIONS
 // ======================================================
 
+// ------------------------------------------------------
+// CLOSURES
+// ------------------------------------------------------
+
+closure = { type_expr? ~ "|" ~ param_list ~ "|" }
+
 // ------------------------------------------------------
 // TUPLES & ARRAYS
 // ------------------------------------------------------
@@ -549,7 +559,8 @@ not_px     = { "!" }
 neg_px     = { "-" }
 
 prefix = {
-    deref_px
+    closure
+  | deref_px
   | mut_ref_px
   | ref_px
   | new_px

crates/parser/src/parser/common/expr.rs

@@ -3,6 +3,7 @@ use crate::{
     ast::*,
     ast_ensure, ast_expr,
     error::{AstError, AstResult, GetLength, IntoErr, collect_recovered, collect_recovered_map},
+    parser::consume_rule,
 };
 use pest::pratt_parser::PrattParser;
 use std::sync::OnceLock;
@@ -12,7 +13,7 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Expression {
 
     fn try_from(pair: pest::iterators::Pair<'a, Rule>) -> Result<Self, Self::Error> {
         let rule = pair.as_rule();
-        let inner = pair.clone().into_inner();
+        let mut inner = pair.clone().into_inner();
 
         match rule {
             Rule::expr => {
@@ -78,6 +79,15 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Expression {
             Rule::static_path => ast_expr!(Expression::Path(pair.try_into())),
             Rule::literal => ast_expr!(Expression::Literal(pair.try_into())),
             Rule::expr_path => ast_expr!(Expression::Path(pair.try_into())),
+            Rule::statement_wrapper => {
+                let i = inner.next().unwrap();
+                match i.as_rule() {
+                    Rule::expr => i.try_into(),
+                    _ => ast_expr!(Expression::Statement(
+                        i.try_into().get_map(Box::new).map(Box::new)
+                    )),
+                }
+            }
             Rule::statement | Rule::basic_stmt | Rule::control_flow => ast_expr!(
                 Expression::Statement(pair.try_into().get_map(Box::new).map(Box::new))
             ),
@@ -104,6 +114,16 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Prefix {
             ),
             Rule::not_px => Self::Not,
             Rule::neg_px => Self::Neg,
+            Rule::closure => {
+                let mut inner = pair.into_inner();
+
+                return ast_expr!(Self::Closure(
+                    consume_rule(&mut inner, Rule::type_expr)
+                        .map(TypeExpr::try_from)
+                        .transpose(),
+                    collect_recovered(inner.next().unwrap().into_inner())
+                ));
+            }
 
             _ => return AstError::bug_unimplemented(pair),
         })

crates/parser/src/parser/common/statement.rs

@@ -18,6 +18,24 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Block {
     }
 }
 
+impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for StatementBody {
+    type Error = AstError<'a, Self>;
+
+    fn try_from(pair: pest::iterators::Pair<'a, Rule>) -> Result<Self, Self::Error> {
+        let mut inner = pair.clone().into_inner();
+
+        ast_ensure!(pair, Rule::statement_body => {
+            let i = inner.next().unwrap();
+
+            match i.as_rule() {
+                Rule::expr => ast_expr!(StatementBody::Expression(i.try_into())),
+                Rule::statement_wrapper => ast_expr!(StatementBody::Statement(i.try_into())),
+                _ => AstError::bug_unimplemented(i),
+            }
+        })
+    }
+}
+
 impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for StatementBranch {
     type Error = AstError<'a, Self>;
 
@@ -63,12 +81,7 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Statement {
                 ast_expr!(Statement::If {
                     initial: inner.next().unwrap().try_into(),
                     else_if: collect_recovered(inner.next().unwrap().into_inner()),
-                    else_branch: inner
+                    else_branch: inner.next().map(StatementBody::try_from).transpose(),
-                        .next()
-                        .map(Expression::try_from)
-                        .transpose()
-                        .map(|v| v.map(Box::new))
-                        .get_map(|v| { Some(Box::new(v)) }),
                 })
             }
 
@@ -87,7 +100,7 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Statement {
                 mutable: Ok(listen_rule(&mut inner, Rule::mutable)) as AstResult<'_, bool>,
                 pattern: inner.next().unwrap().try_into(),
                 iterator: inner.next().unwrap().try_into(),
-                body: inner.next().unwrap().try_into().map(Box::new),
+                body: inner.next().unwrap().try_into(),
             }),
 
             Rule::match_stmt => ast_expr!(Statement::Match(

mist-test/src/event.mist

@@ -1,7 +1,7 @@
 pub enum Event {
     Startup,
     Shutdown,
-    TaskExecuted(String),
+    TaskExecuted[String],
-    PluginLoaded(String),
+    PluginLoaded[String],
-    Error(String),
+    Error[String],
 }

mist-test/src/main.mist

@@ -10,3 +10,19 @@ void main() {
     app_instance.boot();
     app_instance.run();
 }
+
+void do_stuff() {
+    vec!(1, 2, 3).into_iter().map(Option<i32> |var v| {Some(v)}).collect::<Vec<_>>();
+
+    if (43==69) testing1();
+}
+
+i32 testing1() {
+
+    i32 v = if (0 == 0) {
+        0
+    } else {
+        1
+    };
+    v
+}