queries: highlight local closures

runtime/queries/rust/locals.scm

@@ -21,3 +21,18 @@
 
 ; References
 (identifier) @local.reference
+
+; In here, `bar` is a function, as it is equal to a closure:
+;
+; let bar = || 4;
+;
+; After this, we know that `bar` must be a function:
+;
+; let a = bar;
+;         ^^^ function
+;
+; let a = f(bar)
+;           ^^^ function
+(let_declaration
+  pattern: (identifier) @local.definition.function
+  value: (closure_expression))