start of destructure patterns

compiler/can/src/def.rs

@@ -873,7 +873,15 @@ pub(crate) fn sort_can_defs_new(
                                 );
                             }
                         },
-                        _ => todo!("{:?}", &def.loc_pattern.value),
+                        _ => {
+                            declarations.push_destructure_def(
+                                def.loc_pattern,
+                                def.loc_expr,
+                                def.expr_var,
+                                def.annotation,
+                                def.pattern_vars.into_iter().collect(),
+                            );
+                        }
                     }
                 }
             }

compiler/can/src/expr.rs

@@ -2047,6 +2047,34 @@ impl Declarations {
         index
     }
 
+    /// Any def with a weird pattern
+    pub fn push_destructure_def(
+        &mut self,
+        loc_pattern: Loc<Pattern>,
+        loc_expr: Loc<Expr>,
+        expr_var: Variable,
+        annotation: Option<Annotation>,
+        pattern_vars: VecMap<Symbol, Variable>,
+    ) -> usize {
+        let index = self.declarations.len();
+
+        let destruct_def = DestructureDef {
+            loc_pattern,
+            pattern_vars,
+        };
+
+        let destructure_def_index = Index::push_new(&mut self.destructs, destruct_def);
+
+        self.declarations.push(DeclarationTag::Destructure(destructure_def_index));
+        self.variables.push(expr_var);
+        self.symbols.push(Loc::at_zero(Symbol::ATTR_ATTR));
+        self.annotations.push(annotation);
+
+        self.expressions.push(loc_expr);
+
+        index
+    }
+
     pub fn push_def(&mut self, def: Def) {
         match def.loc_pattern.value {
             Pattern::Identifier(symbol) => match def.loc_expr.value {

compiler/can/src/module.rs

@@ -5,7 +5,7 @@ use crate::effect_module::HostedGeneratedFunctions;
 use crate::env::Env;
 use crate::expr::{ClosureData, Declarations, Expr, Output};
 use crate::operator::desugar_def;
-use crate::pattern::Pattern;
+use crate::pattern::{BindingsFromPattern, Pattern};
 use crate::scope::Scope;
 use bumpalo::Bump;
 use roc_collections::{MutMap, SendMap, VecSet};
@@ -526,7 +526,13 @@ pub fn canonicalize_module_defs<'a>(
 
                 index += 1;
             }
-            Destructure(_) => todo!(),
+            Destructure(d_index) => {
+                let destruct_def = &declarations.destructs[d_index.index()];
+
+                for (symbol, _) in BindingsFromPattern::new(&destruct_def.loc_pattern) {
+                    exposed_but_not_defined.remove(&symbol);
+                }
+            }
             MutualRecursion(_) => todo!(),
         }
     }

compiler/collections/src/vec_map.rs

@@ -123,6 +123,15 @@ impl<K: PartialEq, V> VecMap<K, V> {
     }
 }
 
+impl<K: Ord, V> std::iter::FromIterator<(K, V)> for VecMap<K, V> {
+    fn from_iter<T: IntoIterator<Item = (K, V)>>(iter: T) -> Self {
+        let mut this = Self::default();
+        this.extend(iter);
+
+        this
+    }
+}
+
 impl<K: Ord, V> Extend<(K, V)> for VecMap<K, V> {
     #[inline(always)]
     fn extend<T: IntoIterator<Item = (K, V)>>(&mut self, iter: T) {