From ff3edf17e52ba2d487ade7617969843f43100d10 Mon Sep 17 00:00:00 2001
From: Joscha <joscha@plugh.de>
Date: Sat, 19 Nov 2022 19:13:30 +0100
Subject: [PATCH] Parse anonymous function definitions

---
 src/ast/table_destr.rs    |  2 ++
 src/parser.rs             |  1 +
 src/parser/func_defs.rs   | 71 +++++++++++++++++++++++++++++++++++++--
 src/parser/table_destr.rs |  3 +-
 4 files changed, 73 insertions(+), 4 deletions(-)

diff --git a/src/ast/table_destr.rs b/src/ast/table_destr.rs
index 2886985..56c8d36 100644
--- a/src/ast/table_destr.rs
+++ b/src/ast/table_destr.rs
@@ -2,6 +2,8 @@ use crate::span::{HasSpan, Span};
 
 use super::{Expr, Ident, Space};
 
+// TODO Make table patterns recursive
+
 #[derive(Debug, Clone)]
 pub enum TablePatternElem {
     /// `foo`
diff --git a/src/parser.rs b/src/parser.rs
index 7f4a722..6688a5b 100644
--- a/src/parser.rs
+++ b/src/parser.rs
@@ -6,6 +6,7 @@
 //!   made public later.
 
 // TODO Turn multiple calls to subparsers into clone-s
+// TODO Remove unnecessary +Clone-s and 'static-s
 
 mod basic;
 mod expr;
diff --git a/src/parser/func_defs.rs b/src/parser/func_defs.rs
index af6b0f7..0d7b51a 100644
--- a/src/parser/func_defs.rs
+++ b/src/parser/func_defs.rs
@@ -2,10 +2,75 @@ use chumsky::prelude::*;
 
 use crate::ast::{Expr, FuncDef};
 
-use super::basic::Error;
+use super::basic::{ident, space, Error};
+use super::table_destr::table_pattern;
+
+fn func_def_anon_no_arg(
+    expr: impl Parser<char, Expr, Error = Error>,
+) -> impl Parser<char, FuncDef, Error = Error> {
+    text::keyword("function")
+        .ignore_then(space())
+        .then_ignore(just('('))
+        .then(space())
+        .then_ignore(just(')'))
+        .then(space())
+        .then(expr)
+        .map_with_span(|(((s0, s1), s2), body), span| FuncDef::AnonNoArg {
+            s0,
+            s1,
+            s2,
+            body: Box::new(body),
+            span,
+        })
+}
+
+fn func_def_anon_arg(
+    expr: impl Parser<char, Expr, Error = Error>,
+) -> impl Parser<char, FuncDef, Error = Error> {
+    text::keyword("function")
+        .ignore_then(space())
+        .then_ignore(just('('))
+        .then(space())
+        .then(ident())
+        .then(space())
+        .then_ignore(just(')'))
+        .then(space())
+        .then(expr)
+        .map_with_span(
+            |(((((s0, s1), arg), s2), s3), body), span| FuncDef::AnonArg {
+                s0,
+                s1,
+                arg,
+                s2,
+                s3,
+                body: Box::new(body),
+                span,
+            },
+        )
+}
+
+fn func_def_anon_destr(
+    expr: impl Parser<char, Expr, Error = Error>,
+) -> impl Parser<char, FuncDef, Error = Error> {
+    text::keyword("function")
+        .ignore_then(space())
+        .then(table_pattern())
+        .then(space())
+        .then(expr)
+        .map_with_span(|(((s0, pattern), s1), body), span| FuncDef::AnonDestr {
+            s0,
+            pattern,
+            s1,
+            body: Box::new(body),
+            span,
+        })
+}
 
 pub fn func_def(
-    expr: impl Parser<char, Expr, Error = Error>,
+    expr: impl Parser<char, Expr, Error = Error> + Clone + 'static,
 ) -> BoxedParser<'static, char, FuncDef, Error> {
-    todo().boxed()
+    func_def_anon_no_arg(expr.clone())
+        .or(func_def_anon_arg(expr.clone()))
+        .or(func_def_anon_destr(expr))
+        .boxed()
 }
diff --git a/src/parser/table_destr.rs b/src/parser/table_destr.rs
index 8490962..538a6a9 100644
--- a/src/parser/table_destr.rs
+++ b/src/parser/table_destr.rs
@@ -25,7 +25,7 @@ fn table_pattern_elem() -> impl Parser<char, TablePatternElem, Error = Error> +
     named.or(positional)
 }
 
-fn table_pattern() -> impl Parser<char, TablePattern, Error = Error> + Clone {
+pub fn table_pattern() -> BoxedParser<'static, char, TablePattern, Error> {
     let elem = space()
         .then(table_pattern_elem())
         .then(space())
@@ -43,6 +43,7 @@ fn table_pattern() -> impl Parser<char, TablePattern, Error = Error> + Clone {
             trailing_comma,
             span,
         })
+        .boxed()
 }
 
 pub fn table_destr(