Merge pull request #52 from mist-go/parser-patches

Parser patches

crates/codegen/src/lib.rs

@@ -4,10 +4,6 @@ pub mod top_level;
 
 use mist_parser::ast::*;
 
-pub fn get_mutable(mutable: bool) -> String {
-    if mutable { "mut " } else { "" }.to_string()
-}
-
 pub struct Context {
     pub expr_ensure_semicolon: bool,
 }
@@ -238,34 +234,39 @@ impl GetRust for TypeExprKind {
 impl GenRust for Pattern {
     fn gen_rust(&self, ctx: &mut Context, cg: &mut RustCodegen) {
         match self {
-            Self::Id(id) => cg.add(&id.get_rust()),
+            Self::Path(mutable, path) => {
-            Self::Path(path) => cg.add(&path.get_rust()),
+                if *mutable {
+                    cg.add("mut ");
+                };
+
+                cg.add(&path.get_rust())
+            }
             Self::Literal(lit) => lit.gen_rust(ctx, cg),
 
-            Self::Struct(path, ids) => {
+            Self::Struct(path, inner) => {
                 cg.add(&path.get_rust());
                 cg.add(" {");
-                for id in ids {
+                for pat in inner {
-                    cg.add(&id.get_rust());
+                    pat.gen_rust(ctx, cg);
                     cg.add(",");
                 }
                 cg.add("}");
             }
 
-            Self::NamedTuple(path, ids) => {
+            Self::NamedTuple(path, inner) => {
                 cg.add(&path.get_rust());
                 cg.add(" (");
-                for id in ids {
+                for pat in inner {
-                    cg.add(&id.get_rust());
+                    pat.gen_rust(ctx, cg);
                     cg.add(",");
                 }
                 cg.add(")");
             }
 
-            Self::Tuple(ids) => {
+            Self::Tuple(inner) => {
                 cg.add("(");
-                for id in ids {
+                for pat in inner {
-                    cg.add(&id.get_rust());
+                    pat.gen_rust(ctx, cg);
                     cg.add(",");
                 }
                 cg.add(")");

crates/codegen/src/statement.rs

@@ -1,6 +1,6 @@
 use mist_parser::ast::*;
 
-use crate::{Context, get_mutable};
+use crate::Context;
 
 use crate::{GenRust, GetRust, RustCodegen};
 
@@ -59,7 +59,11 @@ impl GenRust for Statement {
                 cg.add(" {");
                 cg.indent += 1;
 
-                for (pat, body) in match_items {
+                for match_item in match_items {
+                    cg.add_indentedln(&match_item.get_comment());
+
+                    let MatchItem(pat, body) = &match_item.item;
+
                     for (i, p) in pat.iter().enumerate() {
                         cg.addln("");
                         cg.add_indented("");
@@ -158,13 +162,11 @@ impl GenRust for Statement {
             }
 
             Statement::For {
-                mutable,
                 pattern,
                 iterator,
                 body,
             } => {
                 cg.add("for ");
-                cg.add(&get_mutable(*mutable));
                 pattern.gen_rust(ctx, cg);
                 cg.add(" in ");
                 iterator.gen_rust(ctx, cg);
@@ -186,8 +188,6 @@ impl GenRust for Statement {
 
 impl GenRust for VarDecl {
     fn gen_rust(&self, ctx: &mut Context, cg: &mut RustCodegen) {
-        cg.add(&get_mutable(self.mutable));
-
         self.name.gen_rust(ctx, cg);
 
         cg.add(

crates/codegen/src/top_level.rs

@@ -212,8 +212,7 @@ impl GenRust for (&Vec<Spanned<FieldDeclStmt>>, &Spanned<ClassConstructor>) {
         cg.add_indentedln("}\n");
 
         let mut constructor_params = vec![VarDecl {
-            mutable: false,
+            name: Pattern::Path(false, Path(vec![Identifier(String::from("self"))])),
-            name: Pattern::Id(Identifier(String::from("self"))),
             type_: Some(TypeExpr(
                 TypeExprKind::Path(Path(vec![Identifier(String::from("Self"))])),
                 vec![TypePostfix::RefMut],

crates/parser/src/ast/expr.rs

@@ -32,12 +32,11 @@ pub enum Literal {
 
 #[derive(Debug, Clone, Serialize)]
 pub enum Pattern {
-    NamedTuple(Path, Vec<Identifier>),
+    NamedTuple(Path, Vec<Box<Pattern>>),
-    Struct(Path, Vec<Identifier>),
+    Struct(Path, Vec<Box<Pattern>>),
-    Tuple(Vec<Identifier>),
+    Tuple(Vec<Box<Pattern>>),
     Literal(Literal),
-    Path(Path),
+    Path(bool, Path),
-    Id(Identifier),
 }
 
 #[derive(Debug, Clone, Serialize)]

crates/parser/src/ast/statement.rs

@@ -31,12 +31,11 @@ pub enum Statement {
         body: StatementBody,
     },
     For {
-        mutable: bool,
         pattern: Pattern,
         iterator: Expression,
         body: StatementBody,
     },
-    Match(Expression, Vec<(Vec<Pattern>, Expression)>),
+    Match(Expression, Vec<Spanned<MatchItem>>),
 
     VarDecl(VarDeclStmt),
     Return(Option<Expression>),
@@ -44,9 +43,11 @@ pub enum Statement {
     Continue,
 }
 
+#[derive(Debug, Clone, Serialize)]
+pub struct MatchItem(pub Vec<Pattern>, pub Expression);
+
 #[derive(Debug, Clone, Serialize)]
 pub struct VarDecl {
-    pub mutable: bool,
     pub name: Pattern,
     pub type_: Option<TypeExpr>,
 }

crates/parser/src/grammar.pest

@@ -134,16 +134,24 @@ literal = {
 // PATTERNS
 // ======================================================
 
+multi_pat_template = _{
+    (pattern ~ ("," ~ pattern)*)?
+}
+
 tuple_pattern = {
-    "[" ~ (identifier ~ ("," ~ identifier)*) ~ "]"
+    "[" ~ multi_pat_template ~ "]"
 }
 
 named_tuple_pattern = {
-    static_path ~ "[" ~ (identifier ~ ("," ~ identifier)*)? ~ "]"
+    static_path ~ "[" ~ multi_pat_template ~ "]"
 }
 
 struct_pattern = {
-    static_path ~ "{" ~ (identifier ~ ("," ~ identifier)*)? ~ "}"
+    static_path ~ "{" ~ multi_pat_template ~ "}"
+}
+
+path_pattern = {
+    mutable? ~ static_path
 }
 
 pattern = _{
@@ -151,7 +159,7 @@ pattern = _{
   | tuple_pattern
   | struct_pattern
   | literal
-  | static_path
+  | path_pattern
 }
 
 // ======================================================
@@ -171,7 +179,7 @@ meta = {
 }
 
 meta_list = {
-    meta ~ ("," ~ meta)* ~ ","?
+    (meta ~ ("," ~ meta)* ~ ","?)?
 }
 
 attributes = {
@@ -182,7 +190,7 @@ attributes = {
 // DECLARATION HELPERS
 // ======================================================
 var_decl = {
-    (var | type_expr) ~ mutable? ~ pattern
+    (var | type_expr) ~ pattern
 }
 
 field = {
@@ -190,11 +198,11 @@ field = {
 }
 
 field_list = {
-    field ~ ("," ~ field)* ~ ","?
+    (field ~ ("," ~ field)* ~ ","?)?
 }
 
 param_list = {
-    var_decl ~ ("," ~ var_decl)* ~ ","?
+    (var_decl ~ ("," ~ var_decl)* ~ ","?)?
 }
 
 // ======================================================
@@ -252,7 +260,7 @@ enum_decl = {
 // ======================================================
 
 class_constructor = {
-    visibility? ~ "constructor" ~ generics_decl? ~ "(" ~ param_list? ~ ")" ~ block
+    visibility? ~ "constructor" ~ generics_decl? ~ "(" ~ param_list ~ ")" ~ block
 }
 
 class_fields = {
@@ -268,7 +276,7 @@ self_param = {
 }
 
 method = {
-    visibility? ~ type_expr ~ identifier ~ generics_decl? ~ "(" ~ self_param? ~ ("," ~ param_list?)? ~ ")" ~ block
+    visibility? ~ type_expr ~ identifier ~ generics_decl? ~ "(" ~ self_param? ~ ("," ~ param_list)? ~ ")" ~ block
 }
 
 class_item = _{
@@ -297,7 +305,7 @@ impl_decl = {
 trait_requirements = { ":" ~ type_expr_param ~ ("+" ~ type_expr_param)* }
 
 method_no_body = {
-    visibility? ~ type_expr ~ identifier ~ generics_decl? ~ "(" ~ self_param? ~ ("," ~ param_list?)? ~ ")" ~ semicolon
+    visibility? ~ type_expr ~ identifier ~ generics_decl? ~ "(" ~ self_param? ~ ("," ~ param_list)? ~ ")" ~ semicolon
 }
 
 trait_item = _{
@@ -314,7 +322,7 @@ trait_decl = {
 // ======================================================
 
 function_decl = {
-    visibility? ~ type_expr ~ identifier ~ "(" ~ param_list? ~ ")" ~ block
+    visibility? ~ type_expr ~ identifier ~ "(" ~ param_list ~ ")" ~ block
 }
 
 // ======================================================
@@ -415,7 +423,7 @@ c_for_stmt = {
 }
 
 for_stmt = {
-    "for" ~ "(" ~ mutable? ~ pattern ~ ":" ~ expr ~ ")" ~ statement_body
+    "for" ~ "(" ~ pattern ~ ":" ~ expr ~ ")" ~ statement_body
 }
 
 loop_stmt = {

crates/parser/src/parser/common/decl.rs

@@ -2,8 +2,7 @@ use crate::{
     Rule,
     ast::*,
     ast_expr,
-    error::{AstError, AstResult, IntoErr},
+    error::{AstError, IntoErr},
-    parser::listen_rule,
 };
 
 impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for VarDeclStmt {
@@ -63,13 +62,10 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for VarDecl {
                     })
                     .transpose();
 
-                let mutable: AstResult<'_, bool> = Ok(listen_rule(&mut inner, Rule::mutable));
-
                 let name = Pattern::try_from(inner.next().unwrap());
 
                 ast_expr!(VarDecl {
                     type_: type_,
-                    mutable: mutable,
                     name: name,
                 })
             }

crates/parser/src/parser/common/mod.rs

@@ -7,8 +7,8 @@ use crate::{
     Rule,
     ast::*,
     ast_ensure, ast_expr,
-    error::{AstError, IntoErr, collect_recovered},
+    error::{AstError, AstResult, IntoErr, collect_recovered, collect_recovered_map},
-    parser::consume_rule,
+    parser::{consume_rule, listen_rule},
 };
 
 impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Identifier {
@@ -60,23 +60,26 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Pattern {
         let mut inner = pair.clone().into_inner();
 
         match rule {
-            Rule::tuple_pattern => ast_expr!(Pattern::Tuple(collect_recovered(pair.into_inner()))),
+            Rule::tuple_pattern => ast_expr!(Pattern::Tuple(collect_recovered_map(inner, |v| {
+                Self::try_from(v).map(Box::new)
+            }))),
 
             Rule::named_tuple_pattern => ast_expr!(Pattern::NamedTuple(
                 Path::try_from(inner.next().unwrap()),
-                collect_recovered(inner),
+                collect_recovered_map(inner, |v| Self::try_from(v).map(Box::new)),
             )),
 
             Rule::struct_pattern => ast_expr!(Pattern::Struct(
                 Path::try_from(inner.next().unwrap()),
-                collect_recovered(inner),
+                collect_recovered_map(inner, |v| Self::try_from(v).map(Box::new)),
             )),
 
             Rule::literal => ast_expr!(Pattern::Literal(pair.try_into())),
 
-            Rule::identifier => ast_expr!(Pattern::Id(pair.try_into())),
+            Rule::path_pattern => ast_expr!(Pattern::Path(
-
+                Ok(listen_rule(&mut inner, Rule::mutable)) as AstResult<'_, bool>,
-            Rule::static_path => ast_expr!(Pattern::Path(pair.try_into())),
+                inner.next().unwrap().try_into()
+            )),
 
             _ => AstError::bug_unimplemented(pair),
         }

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

@@ -2,8 +2,7 @@ use crate::{
     Rule,
     ast::*,
     ast_ensure, ast_expr,
-    error::{AstError, AstResult, IntoErr, collect_recovered},
+    error::{AstError, IntoErr, collect_recovered},
-    parser::listen_rule,
 };
 
 impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Block {
@@ -97,7 +96,6 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Statement {
             }),
 
             Rule::for_stmt => ast_expr!(Statement::For {
-                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(),
@@ -105,18 +103,23 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for Statement {
 
             Rule::match_stmt => ast_expr!(Statement::Match(
                 inner.next().unwrap().try_into(),
-                inner
+                collect_recovered(inner),
-                    .map(|match_itms| {
-                        let mut match_inner = match_itms.into_inner();
-                        Ok((
-                            collect_recovered(match_inner.next().unwrap().into_inner()).get()?,
-                            Expression::try_from(match_inner.next().unwrap()).get()?,
-                        ))
-                    })
-                    .collect::<AstResult<'a, Vec<_>>>(),
             )),
 
             _ => AstError::bug_unimplemented(pair),
         }
     }
 }
+
+impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for MatchItem {
+    type Error = AstError<'a, Self>;
+
+    fn try_from(pair: pest::iterators::Pair<'a, Rule>) -> Result<Self, Self::Error> {
+        let mut match_inner = pair.into_inner();
+
+        Ok(MatchItem(
+            collect_recovered(match_inner.next().unwrap().into_inner()).get()?,
+            Expression::try_from(match_inner.next().unwrap()).get()?,
+        ))
+    }
+}

crates/parser/src/parser/items/function.rs

@@ -23,14 +23,11 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for FunctionDecl {
 
             let self_param = consume_rule(&mut inner, Rule::self_param).map(|param| {
                 let mut param_inner = param.into_inner();
-                let name = Pattern::Id(Identifier(String::from("self")));
-
                 let mutable = listen_rule(&mut param_inner, Rule::mutable);
-
                 let is_ref = listen_rule(&mut param_inner, Rule::deref_px);
+                let name = Pattern::Path(mutable && !is_ref, Path(vec![Identifier(String::from("self"))]));
 
                 VarDecl {
-                    mutable: mutable && !is_ref,
                     name: name.clone(),
                     type_: Some(TypeExpr(
                         TypeExprKind::Path(Path(vec![Identifier("Self".to_string())])),