review: use parser suggestion

crates/reporting/src/error/parse.rs

@@ -249,10 +249,11 @@ fn to_expr_report<'a>(
 
                     Context::InDef(_pos) => {
                         vec![alloc.stack([
-                            alloc.concat([alloc.reflow(
+                            alloc.reflow("Looks like you are trying to define a function. "),
-                                "Did you mean to define a function? Condider defining this as",
+                            alloc.reflow("In roc, functions are always written as a lambda, like "),
-                            )]),
+                            alloc
-                            alloc.vcat(vec![alloc.text("id = \\x -> x")]),
+                                .parser_suggestion("increment = \\n -> n + 1")
+                                .indent(4),
                         ])]
                     }
 

crates/reporting/tests/test_reporting.rs

@@ -5653,9 +5653,11 @@ All branches in an `if` must have the same type!
     4│      main = 5 -> 3
                      ^^
 
-    Did you mean to define a function? Condider defining this as
+    Looks like you are trying to define a function. 
 
-    id = \x -> x
+    In roc, functions are always written as a lambda, like 
+
+        increment = \n -> n + 1
     "###
     );